Emissive polymers and devices incorporating these polymers

ABSTRACT

The present invention relates to a class of luminescent and conductive polymer compositions having chromophores, and particularly solid films of these compositions exhibiting increased luminescent lifetimes, quantum yields and amplified emissions. These desirable properties can be provided through polymers having rigid groups designed to prevent polymer reorganization, aggregation or π-stacking upon solidification. These polymers can also display an unusually high stability with respect to solvent and heat exposures. The invention also relates to a sensor and a method for sensing an analyte through the luminescent and conductive properties of these polymers. Analytes can be sensed by activation of a chromophore at a polymer surface. Analytes include aromatics such as heterocycles, phosphate ester groups and in particular explosives and chemical warfare agents in a gaseous state. The present invention also relates to devices and methods for amplifying emissions by incorporating a polymer having an energy migration pathway and/or providing the polymer as a block co-polymer or as a multi-layer.

RELATED APPLICATION

This application is a continuation-in-part of U.S. patent applicationSer. No. 10/324,064, filed Dec. 18, 2002, which is a continuation ofU.S. patent application Ser. No. 09/305,379, filed May 5, 1999, nowabandoned, which claims the benefit under Title 35, U.S.C. §119(e) ofU.S. Provisional Application No. 60/084,247, filed May 5, 1998.

STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT

This invention was made with government support under grant numberDAAD19-02-D-0002 awarded by the Army. The government has certain rightsin this invention.

FIELD OF THE INVENTION

The present invention relates to a class of luminescent and conductivepolymer compositions, and particularly solid films of these compositionsexhibiting increased luminescent lifetimes, quantum yields and amplifiedemissions. The invention also relates to a sensor and a method forsensing an analyte through the luminescent and conductive properties ofthese polymers.

BACKGROUND OF THE INVENTION

There is a high demand for chemical sensor devices for detecting lowconcentration levels of analytes present in the liquid and gaseousphase. Specificity to particular analytes is also generally desired.

Chemical sensor devices often involve luminescent materials becauseluminescence lifetimes and intensities can be sensitive to the presenceof external species or analytes. Fluorescent polymeric materials areparticularly advantageous for sensor devices because the resultingfluorescence and other physical properties can be optimized and/ortailored for particular analytes through chemical structure changes ofthe polymer.

Charge conducting polymers are usually fluorescent polymers. Suchpolymers are capable of delocalizing charge throughout a substantialportion of the polymer by π-conjugation. The π-conjugated portioncomprises a set of orbitals that can function as a valence band. Thepolymers can be doped with species that either donate or accept electrondensity, and an energy difference between the valence band andconduction band is referred to as a band gap. Moreover, other energylevels may be available in the band gap or in higher energy levelshaving antibonding character.

Because charge delocalization results in the formation of various highlying energy levels, a variety of excited state structures are availableupon absorption of energy by the conducting polymer. The luminescenceyields of these excited state structures depend highly on polymerstructure. The luminescence can be quenched by the presence of speciescapable of absorbing the energy contained by the polymer, resulting inthe polymer returning to a ground state. The species can be an externalspecies or internally located within the polymer, such as a side-group.One example of such quenching by internal species is through aπ-stacking mechanism. Atoms involved in the π-conjugation can bepositioned on top of other groups having geometrically accessibleπ-orbitals, forming a pathway for energy transfer.

Luminescent polymers are disclosed in U.S. Pat. No. 5,414,069 whichdescribes an electroluminescent polymer having a main chain and aplurality of side chains. The main chain contains methylene or oxidegroups and the side chains contain the electroluminescent groups suchthat the electroluminescent groups are not conjugated with one another.One method of modulating electroluminescent properties is by varying thespacing between the electroluminescent groups.

U.S. Pat. No. 5,597,890 relates to π-conjugated polymers that formexciplexes with electron donor or acceptor components. The polymer has amain chain of unsaturated units such as carbon-carbon double and triplebonds and aromatic groups. The side chains include single ring arylgroups.

Thus there remains a need to design polymers having maximal luminescentlifetimes for use in sensory devices, in particular where theluminescent properties are sensitive to the presence of specificanalytes.

SUMMARY OF THE INVENTION

The present invention relates to polymeric compositions capable ofemitting radiation and exhibiting increased luminescent lifetimes andquantum yields. These compositions can be tailored to prevent π-stackingor interactions with acceptor species that can quench the luminescence.The polymers have sufficient rigidity through design of the polymerbackbone and/or side groups which not only optimizes optical propertiesbut imparts enhanced polymer stability. The invention also providesdevices such as sensors which incorporate films of these polymericcompositions.

One aspect of the invention provides a sensor comprising a filmincluding a polymer. The polymer includes a chromophore and the polymeris capable of emitting radiation with a quantum yield of at least about0.05 times that of a quantum yield of the polymer in solution.

Another aspect of the present invention provides a method for amplifyingan emission. The method comprises providing an article comprising apolymer having an energy migration pathway and a chromophore. Thearticle is exposed to a source of energy to form an excitation energy.The excitation energy is allowed to travel through the migration pathwayand to transfer to the chromophore, causing an emission that is greaterthan an emission resulting from a polymer free of an energy migrationpathway.

Another aspect of the present invention provides a method for amplifyingan emission. The method involves providing an article comprising apolymer having an energy migration pathway. The polymer has reducedπ-stacking. The article is exposed to a source of energy from anexcitation energy. The excitation energy is allowed to travel throughthe migration pathway to cause an emission that is greater than anemission resulting from a polymer free of an energy migration pathway.

Another aspect of the present invention provides a sensor. The sensorcomprises an article having at least one layer including a polymericcomposition and a chromophore. The article further comprises anactivation site where the chromophore is capable of activation by ananalyte at the activation site. The sensor also comprises an energymigration pathway within the polymeric composition where energy can betransferred from the pathway to the activation site.

Another aspect of the present invention provides a sensor comprising apolymer capable of emission. The emission is variable and sensitive toan electric field of a medium surrounding the sensor.

Another aspect of the present invention provides a sensor comprising apolymer capable of emission. The emission is variable and sensitive to adielectric constant of a medium surrounding the sensor.

Another aspect of the present invention provides an amplificationdevice. The device comprises a polymer having an energy migrationpathway capable of transporting an excitation energy. The device furthercomprises a chromophore in electronic communication with the energymigration pathway where the chromophore is capable of emitting anenhanced radiation.

Another aspect of the invention provides a polymeric composition. Thecomposition comprises a conjugated π-backbone, the π-backbone comprisinga plane of atoms. A first group and a second group is attached to theπ-backbone, the first group having a first fixed height above the planeand the second group having a second fixed height below the plane. A sumof the first and second heights is at least about 4.5 Å.

Another aspect of the invention provides a sensor which includes apolymeric article comprising the structure:

A and C are aromatic groups and B and D are selected from the groupconsisting of a carbon-carbon double bond and a carbon-carbon triplebond. Any hydrogen on aromatic group A and C can be replaced by E and Frespectively, a and b being integers which can be the same or differentand a=0-4, b=0-4 such that when a=0, b is nonzero and when b=0, a isnonzero, and at least one of E and F includes a bicyclic ring systemhaving aromatic or non-aromatic groups optionally interrupted by O, S,NR¹ and C(R¹)₂ wherein R¹ is selected from the group consisting ofhydrogen, C₁-C₂₀ alkyl, C₁-C₂₀ alkoxy and aryl. The value n is less thanabout 10,000. The sensor further comprises a source of energy applicableto the polymeric composition to cause emission of radiation and a devicefor detecting the emission.

Another aspect of the invention provides a method for detecting thepresence of an analyte. The method provides a polymeric articlecomprising the structure:

A and C are aromatic groups and B and D are selected from the groupconsisting of a carbon-carbon double bond and a carbon-carbon triplebond. Any hydrogen on aromatic group A and C can be replaced by E and Frespectively, a and b being integers which can be the same or differentand a=0-4, b=0-4 such that when a=0, b is nonzero and when b=0, a isnonzero, and at least one of E and F includes a bicyclic ring systemhaving aromatic or non-aromatic groups optionally interrupted by O, S,NR¹ and C(R¹)₂ wherein R¹ is selected from the group consisting ofhydrogen, C₁-C₂₀ alkyl, C₁-C₂₀ alkoxy and aryl. The value n is less thanabout 10,000. The method further includes exposing the polymericcomposition to a source of energy to cause a first emission ofradiation. The polymeric composition is then exposed to a mediumsuspected of containing an analyte, causing a second emission ofradiation. The method involves detecting a difference between the firstemission and the second emission.

Another aspect of the invention provides a field-effect transistorincluding an insulating medium having a first side and an opposingsecond side and a polymeric article positioned adjacent the first sideof the insulating medium. A first electrode is electrically connected toa first portion of the polymeric article and a second electrode iselectrically connected to a second portion of the polymeric article.Each electrode is positioned on the first side of the insulating medium,and the first electrode is further connected to the second electrode byan electrical circuit external of the polymeric structure. A gateelectrode is positioned on the second side of the insulating medium in aregion directly opposite the polymeric article where the gate electrodeis also connected to a voltage source. A source of electromagneticradiation is positioned to apply the electromagnetic radiation to thearticle. At least one species is associated with the article. The atleast one species, upon exposing the polymeric article to theelectromagnetic radiation, is a component of an excited state structure.

Another aspect of the invention provides a sensor comprising aluminescent polymer comprising a hydrogen-bond donor, wherein thehydrogen-bond donor is capable of interacting with an analyte to form acomplex between the hydrogen-bond donor and the analyte, the complexbeing capable of interacting with the luminescent polymer and causingthe luminescent polymer to signal the presence of the analyte, wherein,in the absence of the hydrogen-bond donor, the analyte is less capableof interacting with the luminescent polymer.

The present invention also provides methods for determination of ananalyte comprising providing a luminescent polymer comprising ahydrogen-bond donor; exposing the luminescent polymer to a samplesuspected of containing an analyte, wherein the analyte, if present,interacts with the hydrogen-bond donor to cause a change in theluminescence of the polymer; and determining the change in theluminescence of the polymer, thereby determining the analyte, wherein,in the absence of the hydrogen-bond donor, the analyte produces a lowerdegree of change in the luminescence of the polymer.

Other advantages, novel features, and objects of the invention willbecome apparent from the following detailed description of the inventionwhen considered in conjunction with the accompanying drawings, which areschematic and which are not intended to be drawn to scale. In thefigures, each identical or nearly identical component that isillustrated in various figures is represented by a single numeral. Forpurposes of clarity, not every component is labeled in every figure, noris every component of each embodiment of the invention shown whereillustration is not necessary to allow those of ordinary skill in theart to understand the invention.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 shows a schematic of a film comprising a polymer having achromophore positioned on a surface of the polymer;

FIG. 2 shows a schematic of a rigid side group having fixed heightsabove and below a π-backbone plane;

FIG. 3 shows fluorescence spectra of (a) polymer A before and afterheating polymer A to 140° C. for 10 minutes; (b) polymer A before andafter washing polymer A to methanol for 5 min; (c) polymer X before andafter heating polymer X to 140° C. for five minutes; (d) polymer Xbefore and after washing polymer X with methanol for 5 min.;

FIG. 4 shows solid state and solution absorption and emission spectrafor (a) polymer A; (b) polymer X;

FIG. 5 shows emission spectra for polymer C and an exciplex bandincluding polymer C;

FIG. 6 shows emission spectra over time of (a) polymer A in the absenceand presence of dinitrotoluene (DNT) vapor; (b) polymer A in the absenceand presence of trinitrotoluene (TNT) vapor; (c) polymer A in theabsence and presence of benzoquinone vapor; (d) polymer B in the absenceand presence of DNT; (e) polymer A in the absence and presence of TNTand an inset shows a plot of percent quenching versus time.

FIG. 7 shows a schematic of a field-effect transistor;

FIG. 8 shows a schematic synthesis of (a) the polymerization ofpoly(phenyleneethynylene) on phenyliodide functionalized resin; (b)ethyl ester end functionalized poly(phenyleneethynylene);

FIG. 9 shows a schematic synthesis of (a) polymer A and polymer B; (b)polymer C;

FIG. 10 shows a schematic synthesis of (a) polymer synthesis withmonomer DD; (b) monomer 1,4-Dinaphthyl-2,5-diacetylidebenzene (DD);

FIG. 11A schematically shows amplified emission of two polymers inseries;

FIG. 11B schematically shows amplified emission of a multi-layer ofpolymers in series;

FIG. 12 shows a plot of enhanced sensitivity of the sensor for TNT whena donor polymer is in series with an acceptor polymer;

FIG. 13 shows a schematic of a multi-layer sensor having a gradient ofenergy band gaps and an activated chromophore at a surface of themulti-layer;

FIG. 14 shows a range of emissions for transporter chromophore A and avariety of polymers B-F;

FIG. 15 shows polymers A-D that are capable of detecting the presence ofTNT vapor, as indicated by an intensity plot over time;

FIG. 16 shows a fluorescence intensity plot displaying a variation inintensities for an “all-iptycene” polymer

FIG. 17 shows a schematic synthesis of a monomer having acetylenefunctional groups;

FIG. 18 shows a schematic synthesis for the preparation ofacetylene-based polymers;

FIG. 19 shows examples of polymer structures that can providehydrogen-bonding interactions as well as charge-transfer interactions;

FIG. 20 shows examples of electron-poor polymer structures;

FIG. 21 shows an example of a polymer structure having fluoride groupsand displaying spectral data in the presence of TNT;

FIG. 22 shows an example of groups that are reactive with phosphateester groups;

FIG. 23 shows a schematic of a polymer having rigid groups that reduceπ-stacking interactions between polymer backbones;

FIG. 24 shows an example of a polymer structure substituted withfluorinated alcohol groups for hydrogen bonding nitro groups;

FIG. 25 shows an example of an exciplex structure formed in the presenceof a cation and emission intensity data upon binding a cation;

FIG. 26 shows a schematic synthesis of a polymer containing a crownether;

FIG. 27 shows examples of polymer structures having groups capable ofbinding cations;

FIG. 28 shows examples of triphenylene-based polymer structures;

FIG. 29 shows an example of a cyclophane polymer structure;

FIG. 30 shows a schematic synthesis of a triphenylene-based monomer;

FIG. 31 shows a schematic synthesis of a triphenylene-based monomer;

FIG. 32 shows examples of triphenylene-based polymer structures; and

FIG. 33 shows a device comprising a transparent support coated with apolymer film capable of amplifying emission through sequential emissionend re-absorption cycles.

FIG. 34 shows a schematic synthesis of a monomer having ahexafluoroisopropanol group, according to one embodiment of the presentinvention.

FIG. 35 shows a schematic synthesis of a monomer having twohexafluoroisopropanol groups, according to one embodiment of the presentinvention.

FIG. 36 shows a schematic synthesis of a polymers containinghexafluoroisopropanol groups.

FIG. 37 shows the average changes in fluorescence emission intensity ofvarious luminescent polymers upon repeated exposures to equilibriumvapor pressures of several analytes.

FIG. 38 shows the real-time fluorescence response of (a) polymer P1 tofive separate 3 second exposures to pyridine vapor, (b) polymer P2 to asingle 3 second exposure to pyridine vapor, and (c) polymer P3 to asingle 3 second exposure to pyridine vapor.

DETAILED DESCRIPTION

The present invention relates to polymer films exhibiting enhancedoptical properties such as luminescent lifetimes, amplified emissions,enhanced stabilities and devices such as sensors which incorporate thesepolymer films. The sensors may be capable of determining, for example,aromatic compounds including heterocycles, compounds comprisingphosphate ester groups, and/or explosives and chemical warfare agents.

One aspect of the invention provides a sensor comprising a film. A“sensor” refers to any device or article capable of detecting ananalyte. In one embodiment, the film comprises a polymer where thepolymer includes a chromophore. Polymers are extended molecularstructures comprising a backbone which optionally contain pendant sidegroups, where “backbone” refers to the longest continuous bond pathwayof the polymer. A “chromophore” refers to a species that can eitherabsorb or emit electromagnetic radiation. In a preferred embodiment, thechromophore is capable of absorbing or emitting radiation in theUV-visible range, i.e. absorbed or emitted energy involving excitedelectronic states. In one embodiment, the chromophore is a conjugatedgroup. A “conjugated group” refers to an interconnected chain of atleast three atoms, each atom participating in delocalized π-bonding.

A polymer including a chromophore can absorb a quantum ofelectromagnetic radiation to cause the polymer to achieve an excitedstate structure. In one embodiment, the polymer is an emissive polymercapable of emitting radiation. Radiation can be emitted from achromophore of the polymer. In one embodiment, the emitted radiation isluminescence, in which “luminescence” is defined as an emission ofultraviolet or visible radiation. Specific types of luminescence include“fluorescence” in which a time interval between absorption and emissionof visible radiation ranges from 10⁻¹² to 10⁻⁷ s. “Chemiluminescence”refers to emission of radiation due to a chemical reaction, whereas“electrochemiluminescence” refers to emission of radiation due toelectrochemical reactions. If the chromophore is a conjugated group, theextent of delocalized bonding allows the existence of a number ofaccessible electronic excited states. If the conjugation is so extensiveso as to produce a near continuum of excited states, electronicexcitations can involve a valence band, the highest fully occupied band,and a conduction band.

Typically, fluorescence is “quenched” when a chromophore in an excitedstate is exposed to an “acceptor” species that can absorb energy fromthe excited state chromophore. The excited state chromophore returns toa ground state due to nonradiative processes (i.e. without emittingradiation), resulting in a reduced quantum yield. A “quantum yield”refers to a number of photons emitted per adsorbed photon. Thus, theexcited state chromophore can function as a “donor” species in that ittransfers energy to the acceptor species. The acceptor species can be anexternal molecule such as another polymer or an internal species such asanother portion of the same polymer.

In particular, when a polymer includes conjugated portions, the polymercan undergo a phenomena known as “π-stacking,” which involves cofacialinteractions between π-orbitals of the conjugated portions. If thepolymer includes a conjugated chromophore, a π-stacking arrangement canfacilitate energy transfer between donor and acceptor species andincrease the likelihood of quenching. The capability for π-stacking isconsiderably enhanced when the polymer is in the solid state, i.e. notin solution.

It is an advantageous feature of the present invention to provide apolymer including a chromophore, where the polymer has a molecularstructure that reduces π-stacking interactions, resulting in increasedquantum yields and/or luminescence lifetimes. It is particularlyadvantageous that these enhanced properties can be achieved when thepolymer is provided as a solid state material, e.g. a film. In oneembodiment, the film comprising a polymer including a chromophore has aquantum yield of at least about 0.05 times the quantum yield of thepolymer in solution, more preferably at least about 0.1 times thequantum yield of the polymer in solution, more preferably at least about0.15 times the quantum yield of the polymer in solution, more preferablyat least about 0.2 times the quantum yield of the polymer in solution,more preferably at least about 0.25 times the quantum yield of thepolymer in solution, more preferably at least about 0.3 times thequantum yield of the polymer in solution, more preferably at least about0.4 times the quantum yield of the polymer in solution, and morepreferably still about 0.5 times the quantum yield of the polymer insolution.

In one embodiment, the polymer backbone includes at least onechromophore. Preferably, the backbone includes a plurality ofchromophores optionally interrupted by conjugated or non-conjugatedgroups. In one embodiment, the polymer backbone includes a plurality ofchromophores interrupted by non-conjugated groups. Non-conjugated groupsinclude saturated units such as a chain of alkyl groups optionallyinterrupted by heteroatoms. In one embodiment, the polymer backboneincludes a chromophore attached as a pendant group. The backbone can beeither conjugated or non-conjugated.

In one embodiment, at least a portion of the polymer is conjugated, i.e.the polymer has at least one conjugated portion. By this arrangement,electron density or electronic charge can be conducted along the portionwhere the electronic charge is referred to as being “delocalized.” Eachp-orbital participating in conjugation can have sufficient overlap withadjacent conjugated p-orbitals. In one embodiment, the conjugatedportion is at least about 30 Å in length. In another embodiment, theentire backbone is conjugated and the polymer is referred to as a“conjugated polymer.” Polymers having a conjugated π-backbone capable ofconducting electronic charge are typically referred to as “conductingpolymers.” In the present invention the conducting polymers can eithercomprise chromophore monomeric units, or chromophores interspersedbetween other conjugated groups. Typically, atoms directly participatingin the conjugation form a plane, the plane arising from a preferredarrangement of the p-orbitals to maximize p-orbital overlap, thusmaximizing conjugation and electronic conduction. An example of aconjugated π-backbone defining essentially a plane of atoms are thecarbon atoms of a polyacetylene chain.

In one embodiment, the polymer is selected from the group consisting ofpolyarylenes, polyarylene vinylenes, polyarylene ethynylenes and ladderpolymers, i.e. polymers having a backbone that can only be severed bybreaking two bonds. Examples of such polymers include polythiophene,polypyrrole, polyacetylene, polyphenylene and substituted derivativesthereof. Examples of ladder polymers are:

In these examples, monomeric units can combine to form a chromophore.For example, in polythiophene, the chromophore comprises about thiophenegroups.

By reducing the extent of luminescence quenching, luminescence lifetimesare increased and thus excitation energy can travel along a longerpathway in the polymer. The pathway is referred to as an “energymigration pathway” which can efficiently transport excitation energy,preferably electronic excitation energy. In one embodiment, the pathwayhas a length of at least about 30 Å. In one embodiment, the pathwaycomprises a series of electronic energy states accessible to theexcitation energy.

A chromophore can have different functions in a polymer. For example,physical characteristics of a chromophore can be affected by detectionof an analyte. This type of chromophore is referred to as a “reporterchromophore” which reports the detection of an analyte. A reporterchromophore can be bonded to the polymer or can be an external molecule.A chromophore in the polymer can also function to transport excitationenergy along the polymer and can be referred to as a “transporterchromophore.”

Accompanying this advantageous feature of longer pathways and lifetimesis enhanced amplification of emission. It has been established thatamplification in a polymer is related to a distance over whichexcitation energy can travel. Thus, another aspect of the presentinvention provides a method for amplifying an emission. The methodinvolves providing an article having a polymeric composition having anenergy migration pathway and a chromophore. In one embodiment, thechromophore can be a reporter chromophore. The energy migration pathwaycan be conjugated. Exposing the article to a source of energy forms anexcitation energy which is allowed to travel through the migrationpathway. In one embodiment, migration is enhanced if it occurs in adirection where a HOMO-LUMO gap continually decreases. Energy cantransfer from the pathway to a chromophore to cause an emission ofradiation. In one embodiment, the reporter chromophore can be bonded tothe polymer as a portion of the backbone or as a pendant side group. Inanother embodiment, the reporter chromophore is a molecule external tothe polymer.

In one embodiment, the emission from a reporter chromophore is greaterthan an emission from a reporter chromophore in a polymer that is freeof an energy migration pathway. Polymers that are “free of an energymigration pathway” typically refer to polymers that are incapable ofefficiently transporting excitation energies, e.g. polymers having acompletely carbon-based saturated backbone lacking pendant chromophores.

Energy transfer from the pathway to the reporter chromophore isfacilitated if the chromophore has a HOMO-LUMO gap less than at least aportion of the pathway. To enhance amplification, preferably thereporter chromophore has a HOMO-LUMO gap less than a substantial portionof the pathway, to maximize a distance that the excitation energytravels before transfer to the reporter chromophore.

An example of a film comprising polymer of the present invention isprovided in FIG. 1 which shows polymer 551 having an energy migrationpathway 550. Exposing the polymer to a source of energy 553 results inan excitation energy that can travel along an energy migration pathway550. To “travel along an energy migration pathway” refers to a processby which excitation energy can transfer between accessible energystates. Arrows 555 indicate a direction of travel, and typically thisdirection is dictated by a continual decrease of a HOMO-LUMO gap of theenergy states in the migration pathway. Emission from the polymer,indicated by arrows 554, can result. Polymer 551 has a chromophore thatallows this emission of radiation.

Another aspect of the present invention provides an amplificationdevice. The device comprises a polymer having an energy migrationpathway capable of transporting an excitation energy. As describedabove, the polymer can be exposed to a source of energy which isabsorbed by the polymer as an excitation energy. The excitation energycan travel through the migration pathway and transfer to a chromophorein electronic communication with the energy migration pathway, wherebyan enhanced radiation is emitted from the chromophore. An excitationenergy can transfer from the migration pathway to the chromophore if thechromophore is in electronic communication with the pathway, i.e. thechromophore has accessible energy states by which excitation energytraveling through the migration pathway can transfer. By this device,the emission of any number of polymers can be enhanced.

Another aspect of the present invention provides reduced π-stackinginteractions through the incorporation of rigid groups on the polymer.“Rigid groups” refers to groups that do not easily rotate about a bondaxis, preferably a bond that binds the rigid group to the polymer. Inone embodiment, the rigid group rotates no more than about 180°,preferably no more than about 120° and more preferably no more thanabout 60°. Certain types of rigid groups can provide a polymer with abackbone separated from an adjacent backbone at a distance of at leastabout 4.5 Å and more preferably at least about 5.0 Å. In one embodiment,the rigid groups are incorporated as pendant groups. For example, therigid group may be attached to an aromatic portion of the polymerbackbone to form an iptycene moiety, wherein at least a portion of theiptycene is not planar with the with backbone.

The effect of rigid groups can be schematically illustrated in FIG. 23.Rigid group 382 can be appended onto a polymer backbone 384. The rigidgroups prevent substantial interaction between polymer backbones 384such that cavities 380 are produced. In addition to preventing orreducing the amount of π-stacking, cavities 380 can allow an area forthe entry of analytes 386.

In one embodiment, a polymeric composition is provided having aconjugated π-backbone, the π-backbone comprising essentially a plane ofatoms. A first group and a second group are attached to the π-backboneof the polymeric composition. Both the first and second groups have atleast some atoms that are not planar with the plane of atoms such thatthe atoms can be positioned either below or above the conjugated planeof atoms. It is a feature of the invention that these heights are fixed,the term “fixed height” defined as a height of an atom that is notplanar with the plane of atoms where the atom is free of substantialrotational motion, as described above.

FIG. 2 shows an example of a “fixed height” where side group 26 isbonded to the backbone in a manner that restricts rotational motion. Inthis example, hydrogen atoms 26 and 28 define a fixed height relative toplane 14. The fixed height of sidegroup 26 is defined by hydrogen atom28, having a fixed height above the plane 30 and hydrogen 32 having afixed height below the plane 34. In one embodiment, a sum of the fixedheights is at least about 4.5 Å and more preferably at least about 5.0Å.

It is another feature of the invention that the polymeric composition isrigid with respect to relative orientation between polymers. Typically,polymers have a nonordered structure. Upon polymerization orsolidification, the polymer can orient in a random arrangement. Thisarrangement can change over time, or upon exposure to heat or a solventthat does not dissolve the polymer. In one embodiment, the compositionsof the present invention are rigid to the extent that the polymerarrangement does not substantially change over time, upon exposure tosolvent or upon heating to a temperature of no more than 150° C. Thatis, the rigidity of the side group defining a fixed height does notchange and the height is not affected. In one embodiment, the exposureto solvent or heating step occurs over a period of time of about 5 min.,preferably over a period of time of about 10 min., more preferably about15 min., more preferably about 30 min., and more preferably still about1 h. In one embodiment, the composition is characterized by a firstoptical spectrum having at least one maximum or maxima. The compositionis then exposed to a solvent or heated to a temperature of less thanabout 140° C. and a second optical spectrum is obtained. A maximum ormaxima in the first spectrum differ by no more than about 15 nm from acorresponding maximum or maxima in the second spectrum, preferably themaxima differ by no more than about 10 nm and more preferably the maximadiffer by no more than about 5 nm. In another embodiment, maxima in thesecond spectrum have an intensity change of less than about 10% relativeto the maxima in the first spectrum, and preferably the intensity changeis less than about 15% relative to the maxima in the first spectrum.

An advantage of the present invention is illustrated in FIG. 3. FIG. 3compares various spectra of polymers A (shown below) and polymer X(which does not have sufficient rigidity, shown below) in the solidstate. In FIG. 3( a), an initial fluorescence spectrum 50 of polymer Ais obtained. Polymer A is then heated to 140° C. for 10 minutes andspectrum 52 is obtained. The fluorescence maxima values and fluorescenceintensities are nearly identical, providing evidence that anyreorganization between polymer chains or chemical reorganization withineach chain is insubstantial. In FIG. 3( b), a similar comparison is madebetween an initial spectrum 54 and spectrum 56 for a polymer A, spectrum56 being obtained after exposing the polymer to a solvent such asmethanol for 5 min. In this example, the exposing involves washing thepolymer with methanol. The absorption maxima of spectrum 54 have thesame frequencies as the corresponding maxima in 56, and the intensitiesin 56 decrease by only about 10%, again showing the reorganizationalstability to solvent exposure. In contrast, a comparison of an initialspectrum 58 of planar model polymer X is shown in FIG. 3( c) which showsa substantial differences from fluorescence spectrum 60, taken afterheating the polymer to 140° C. for only five minutes. Not only do thefluorescence maxima occur at different frequencies but the intensitiesdecrease significantly. In FIG. 3( d), the intensities of fluorescencespectrum 62 of polymer X decrease by 15% in spectrum 64 which wasobtained after washing polymer X with methanol for about 5 min.

FIG. 4 shows a comparison of solution and solid state absorption andemission spectra for a polymer allowing π-stacking interactions that canquench luminescence, rendering the polymer ineffective for the uses ofthe invention, versus a polymer of the invention having sufficientrigidity to prevent π-stacking interactions. In FIG. 4( a) absorptionand emission spectra 100 and 102 respectively, are obtained for polymerA in solution. Polymer A has a rigid structure with respect to chainreorganization, such that absorption and emission spectra 104 and 106respectively, obtained for polymer A as a film, show little decrease inintensity. In contrast, FIG. 4( b) shows solution absorption andemission spectra 108 and 110 respectively for polymer X which does nothave a rigid structure in accordance with the features of the invention.The film absorption and emission spectra, 112 and 114 respectively, showsignificant wavelength shifts and a substantial decrease in intensity(the intensity of spectrum 114 has actually been normalized to anincreased intensity to better illustrate the spectral characteristicsand actually has a smaller intensity than shown in FIG. 4( b)).

Some embodiments of the present invention provides polymericcompositions (e.g., luminescent polymers) having the structure,

wherein n is at least 1, A and C are optionally substituted aromaticgroups, and B and D are alkene, alkyne, heteroalkene, or heteroalkyne.

Another aspect of the invention provides a polymeric compositioncomprising the structure:

A and C are optionally substituted aromatic groups. Specifically, anaromatic group is a cyclic structure having a minimum of three atomswith a cyclic, conjugated π-system of p-orbitals, the p-orbitals beingoccupied with 4n+2 electrons, n being a positive integer. B and D areselected from the group consisting of a carbon-carbon double bond and acarbon-carbon triple bond. E and F are attached to aromatic groups A andC respectively and a and b are integers which can be the same ordifferent, a=0-4 and b=0-4 such that when a=0, b is nonzero and whenb=0, a is nonzero. The polymeric composition comprises a conjugatedpi-backbone comprising an aromatic portion, and at least one of E and Fincludes a bicyclic ring system rigidly non-coplanar with the aromaticportion of the conjugated pi-backbone, the bicyclic ring system havingaromatic or non-aromatic groups optionally interrupted by heteroatoms orheteroatom groups such as O, S, N, NR¹, CR¹ and C(R¹)₂ wherein R¹ can beselected from the group consisting of hydrogen, C₁-C₂₀ alkyl, C₁-C₂₀alkoxy and aryl. When E or F is not said bicyclic ring system, E or F isa part of aromatic group A or C. Preferably n is less than about 10,000.In one embodiment, at least one of E and F comprise the first and secondgroups having first and second fixed heights above the π-backbone plane.The preferred features of the composition allow the polymer to haveextensive π-conjugation throughout the polymer. In a preferredembodiment, the polymer is a conducting polymer.

In one embodiment, the polymeric composition has a structure where E_(a)is shown attached to the π-backbone:

G, H, I, and J are aromatic groups, d=1, 2, and d¹=0, 1, such that whend¹=0, d²=0 and when d¹=1, d²=0, 1. Preferably, c is less than about10,000.

In a preferred embodiment, G and H may be the same or different, andeach can be selected from the aromatic group consisting of:

I and J may be the same or different and each can be selected from thegroup consisting of:

Any hydrogen in G, H, I and J can be substituted by R² where R² can beselected from the group consisting of C₁-C₂₀ alkyl, aryl, C₁-C₂₀ alkoxy,phenoxy, C₁-C₂₀ thioalkyl, thioaryl, C(O)OR³, N(R³)(R⁴), C(O)N(R³)(R⁴),F, Cl, Br, NO₂, CN, acyl, carboxylate and hydroxy. R³ and R⁴ can be thesame or different and each can be selected from the group consisting ofhydrogen, C₁-C₂₀ alkyl, and aryl. Z¹ can be selected from the groupconsisting of O, S and NR⁸ where R⁸ can be selected from the groupconsisting of hydrogen, C₁-C₂₀ alkyl, and aryl. Z² can be selected fromthe group consisting of F, Cl, OR³, SR³, NR³R⁴ and SiR⁸R³R⁴.

In one embodiment, A is selected from the group consisting of:

Any hydrogen in A can be substituted by R⁵ where R⁵ can be selected fromthe group consisting of C₁-C₂₀ alkyl, aryl, C₁-C₂₀ alkoxy, phenoxy,C₁-C₂₀ thioalkyl, thioaryl, C(O)OR⁶, N(R⁶)(R⁷), C(O)N(R⁶)(R⁷), F, Cl,Br, NO₂, CN, acyl, carboxylate, hydroxy. R⁶ and R⁷ can be the same ordifferent and each can be selected from the group consisting ofhydrogen, C₁-C₂₀ alkyl, and aryl. Z¹ can be selected from the groupconsisting of O, S and NR⁸ where R⁸ can be selected from the groupconsisting of hydrogen, C₁-C₂₀ alkyl, and aryl. Preferably, A isselected from the group consisting of:

In one embodiment, B and D can be the same or different and each can beselected from the group consisting of:

Any hydrogen in B and D can be substituted by R⁹ where R⁹ can beselected from the group consisting of C₁-C₂₀ alkyl, aryl, C₁-C₂₀ alkoxy,phenoxy, C₁-C₂₀ thioalkyl, thioaryl, C(O)OR¹⁰, N(R¹⁰)(R¹¹),C(O)N(R¹⁰)(R¹¹), F, Cl, Br, NO₂, CN, acyl, carboxylate, hydroxy. R¹⁰ andR¹¹ can be the same or different and each can be selected from the groupconsisting of hydrogen, C₁-C₂₀ alkyl, and aryl. Preferably, B and D are:

In one embodiment, C is selected from the aromatic group consisting of:

R¹² can be selected from the group consisting of hydrogen, C₁-C₂₀ alkyland aryl. Any hydrogen in C can be substituted by R¹³ where R¹³ can beselected from the group consisting of C₁-C₂₀ alkyl, aryl, C₁-C₂₀ alkoxy,phenoxy, C₁-C₂₀ thioalkyl, thioaryl, C(O)OR¹⁴, N(R¹⁴)(R¹⁵),C(O)N(R¹⁴)(R¹⁵), F, Cl, Br, NO₂, CN, acyl, carboxylate, hydroxy. R¹⁴ andR¹⁵ can be the same or different and each can be selected from the groupconsisting of hydrogen, C₁-C₂₀ alkyl, and aryl. Z² can be selected fromthe group consisting of O, S and NR¹⁶ where R¹⁶ can be selected from thegroup consisting of hydrogen, C₁-C₂₀ alkyl, and aryl.

Examples of particularly preferred polymeric compositions having thestructural features in accordance with the invention include:

In one embodiment, at least one of G, H, I and J includes a naphthalenegroup that is a component of an exciplex structure. An “exciplex” isdefined as an excited state transient dimer formed between a donorspecies and an acceptor species. The excited state is formed byphotoexcitation of either the donor or the acceptor. Exciplexes canrepresent an intermediate in a charge transfer process from a donor toan acceptor species. FIG. 5 shows an emission spectrum of a thin filmwith an exciplex feature 122 for polymer C. The normal solution spectrumis shown by curve 120 which does not have an exciplex feature.

In one embodiment, E is selected from the group consisting of:

Any hydrogen in E can be substituted by R¹⁷ where R¹⁷ can be selectedfrom the group consisting of C₁-C₂₀ alkyl, aryl, C₁-C₂₀ alkoxy, phenoxy,C₁-C₂₀ thioalkyl, thioaryl, C(O)OR¹⁸, N(R¹⁸)(R¹⁹), C(O)N(R¹⁸)(R¹⁹), F,Cl, Br, I, NO₂, CN, acyl, carboxylate, hydroxy. R¹⁸ and R¹⁹ can be thesame or different and each can be selected from the group consisting ofhydrogen, C₁-C₂₀ alkyl, and aryl. Z³ can be selected from the groupconsisting of O, S and NR²⁰ where R²⁰ can be selected from the groupconsisting of hydrogen, C₁-C₂₀ alkyl, and aryl.

In one embodiment, the polymeric composition comprises the structure:

Q can be selected from the group consisting of:

R²² can be selected from the group consisting of hydrogen, C₁-C₂₀ alkyland aryl. Any hydrogen in Q can be substituted by R²², R²² can beselected from the group consisting of C₁-C₂₀ alkyl, aryl, C₁-C₂₀ alkoxy,phenoxy, C₁-C₂₀ thioalkyl, thioaryl, C(O)OR²³, N(R²³)(R²⁴),C(O)N(R²⁴)(R²⁵), F, Cl, Br, I, NO₂, CN, acyl, carboxylate, hydroxy. R²³and R²⁴ can be the same or different and each can be selected from thegroup consisting of hydrogen, C₁-C₂₀ alkyl, and aryl. Z⁴ can be selectedfrom the group consisting of O, S and NR²⁵, Z⁵ can be selected from thegroup consisting of N and CR²⁵ and R²⁵ can be selected from the groupconsisting of hydrogen, C₁-C₂₀ alkyl, and aryl. Preferably, n is lessthan about 10,000.

In one embodiment, the polymeric composition comprises the structure:

R²⁶ can be selected from the group consisting of hydrogen, C₁-C₂₀ alkyland aryl. Q is defined as above.

Other specific examples of polymeric compositions having features inaccordance with the invention include:

In another embodiment, the polymeric compositions include triphenylenegroups. FIG. 28 shows examples of triphenylene containing polymers470-478.

Sensors comprising polymeric films also include cyclophane polymer typesas shown in FIG. 29.

Another aspect of the invention provides a sensor that can includepolymeric compositions of the invention. The polymeric compositions ofthe present invention have significant fluorescent yields. Because thefluorescence can be quenched in the presence of an acceptor molecule,the decrease in intensity can serve as a method for determining thepresence or absence of an analyte. The sensor comprises a polymericcomposition comprising the structure:

A, B, C, D, E, F, a and b are defined as above.

The sensor also includes a source of energy applicable to the polymericcomposition to cause radiation emission. The energy can be selected fromthe group consisting of electromagnetic radiation, electrical energy andchemical energy. Preferably, the energy is of a frequency that can beabsorbed by the polymer, resulting in an emission of radiation. Inparticular, when the electromagnetic energy is absorbed by the polymericcomposition, luminescence occurs. Electroluminescence occurs when thecomposition absorbs electrical energy and chemiluminescence results whenthe composition absorbs chemical energy. The sensor also includes adevice for detecting the emission, such as a photomultiplier, aphotodiode or a charge coupled device. The emission detector may bepositionable to detect the emission.

In one embodiment, the sensor also includes an article to provideenhanced rigidity, sensitivity, selectivity, stability, or a combinationof any number of these features, to the ispolymeric composition in thesensor. The article is typically positioned adjacent the polymer and canbe selected from the group consisting of beads, nanoparticles, polymerfibers, waveguides and a film. The article can have a compositionselected from the group consisting of a biological species, a polymer, aceramic, a conductor and a semiconductor. Preferred biological speciesinclude a peptide, an oligonucleotide, an enzyme, an antibody, afluorescent peptide, a fluorescent oligonucleotide and a fluorescentantibody. Examples polymers include polystyrene, polyethylene oxide,polyethylene, polysiloxane, polyphenylene, polythiophene,poly(phenylene-vinylene), polysilane, polyethylene terephthalate andpoly(phenylene-ethynylene). The semiconductor and conductor can beselected from the group consisting of solids and nanoclusters. Preferredsemiconductor materials include Group II/VI, Group III/V and Group IVsemiconductors such as CDS, CdSe, InP, GaAs, Si, Ge and porous silicon.A preferred conductor is colloidal gold. Preferred ceramics includeglass, quartz, titanium oxide and indium tin oxide.

In one embodiment, the article is capable of further enhancing theemission of a polymer. For example, a sensor can be provided comprisinga polymer positioned adjacent a waveguide. Light emitted by the polymerin one can area can be captured by internal reflection in the substrateand then reabsorbed and re-emitted in a different region of the sensor.This process can occur many times before reaching a detector, resultingin a sensor with enhanced sensitivity. Sequential emission andreabsorption cycles increase the probability that an excitation will bequenched or trapped by an analyte. An example of a device that canachieve this effect is shown in FIG. 33 where a transparent support 290is coated with a polymer film of the present invention. The polymer filmis excited by a source of energy 291 on one side of transparent support290 and emission 292 is detected from an edge on an opposite side oftransparent support 290. A further optimization of this device can beachieved by using a waveguide. Excitations in this device can beinitiated at one terminus of the waveguide and most of the lightemerging from an opposite terminus will hav undergone multiple emissionand re-absorption cycles.

Another aspect of the invention provides a method for detecting thepresence of an analyte. The method involves providing a compositioncomprising the structure:

A, B, C, D, E, F, a and b are defined as above. The polymericcomposition is exposed to a source of energy is applicable to thepolymeric composition and the composition achieves an excited state tocause a first emission of radiation. The first emission can befluorescence. The first emission is observed by obtaining an initialemission spectrum of the composition in the absence of the analyte. Theexcited state polymeric composition is then exposed to a mediumsuspected of containing an analyte. In one embodiment, the excited statecomposition is a donor species, the analyte is an acceptor species andelectronic or energy transfer occurs from the excited state compositionto the analyte, providing a route that results in the compositionreturning to ground state accompanied by a decrease in fluorescenceintensity, due to a second emission of radiation. In another embodiment,the excited state composition is an acceptor species and the analyte isa donor species. A difference or change between the first emission andthe second emission provides evidence of the presence of an analyte. Thedifference can be a change in wavelength values or intensity. In somecases, the difference or change comprises a decrease in luminescenceintensity. In some cases, the difference or change comprises an increasein luminescence intensity. Additionally, the difference can be a changein the conductivity. The difference can be caused by an electrontransfer reaction between the composition and the analyte.

In some cases, methods of the invention comprise determining a change inthe wavelength of an emission signal. The wavelength of an emissionsignal refers to the wavelength at which the peak maximum of theemission signal occurs in an emission spectrum. The emission signal maybe a particular peak having the largest intensity in an emissionspectrum (e.g. a fluorescence spectrum), or, alternatively, the emissionsignal may be a peak in an emission spectrum that has at least a definedmaximum, but has a smaller intensity relative to other peaks in theemission spectrum.

In some embodiments, the change in luminescence intensity may occur foran emission signal with substantially no shift in the wavelength of theluminescence (e.g., emission), wherein the intensity of the emissionsignal changes but the wavelength remains essentially unchanged. Inother embodiments, the change in luminescence intensity may occur for anemission signal in combination with a shift in the wavelength of theluminescence (e.g., emission). For example, an emission signal maysimultaneously undergo a shift in wavelength in addition to an increaseor decrease in luminescence intensity. In another embodiment, the changemay comprise two emission signals occurring at two differentwavelengths, wherein each of the two emission signals undergoes a changein luminescence intensity. In some cases, the two emission signals mayundergo changes in luminescence intensity independent of one another. Insome cases, the two emission signals may undergo changes in luminescenceintensity, wherein the two emission signals are associated with oneanother, for example, via an energy transfer mechanism, as describedmore fully below.

In some embodiments, methods of the present invention may furthercomprise determining a change in the wavelength of the luminescence uponexposure of a luminescent polymer to an analyte. That is, in some cases,determination of an analyte may comprise observing a change inluminescence intensity in combination with a change in the luminescencewavelength. For example, the relative luminescence intensities of afirst emission signal and a second emission signal associated with thefirst emission signal may be modulated using the quenching andunquenching methods described herein. In some cases, the first emissionsignal and the second emission signal may be associated with (e.g.,interact with) one another via an energy transfer mechanism, such asfluorescence resonance energy transfer, for example. The term“fluorescence resonance energy transfer” or “FRET” is known in the artand refers to the transfer of excitation energy from an excited statespecies (i.e., FRET donor) to an acceptor species (i.e., FRET acceptor),wherein an emission is observed from the acceptor species. In somecases, the FRET donor may be a luminescent polymer, portion(s) thereof,or other species, such as an analyte. Similarly, the FRET acceptor maybe a luminescent polymer, portion(s) thereof, or other species, such asan analyte.

In one embodiment, a first portion of a luminescent polymer may act asFRET donor and a second portion within the same luminescent polymer mayact as a FRET acceptor, wherein the first portion and the second portioneach have different emission wavelengths. The luminescent polymer may beassociated with a quenching molecule and exist in a “quenched” state,wherein, upon exposure of the first portion to electromagneticradiation, the quenching molecule absorbs the excitation energy andsubstantially no emission is observed. Upon exposure to an analyte, theanalyte may interact with the luminescent polymer and/or quenchingmolecule to “un-quench” the luminescent polymer. As a result, exposureof the first portion to electromagnetic radiation produces anexcited-state, wherein the first portion of the luminescent polymer maytransfer excitation energy to the second portion of the luminescentpolymer, and emission signal from the second portion is observed.

Specificity for a particular analyte by a polymer can be a combinationof size exclusion and functionalization of the polymer. For example,more electron-rich polymers display a higher sensitivity tonitroaromatics. Thus, structure-function relationships can be obtained.

FIG. 17 shows a synthesis of monomer 708 that can be used to formpolymers that are quenched more strongly in the presence of anequilibrium vapor pressure of TNT than that of DNT. In FIG. 17, reactant700 can produce reactant 702 in three steps. By the addition of BuLi inTHF followed by the addition of 80% I₂, molecule 702 can be transformedto 704. Conjugation can be achieved by the addition oftrimethylsilylacetylene to 704 in the presence of 80% Pd(PPh₃)₂Cl₂. TheTMS groups can be achieved from 706 by the addition of 91% KOH/MEOH toachieve monomer 708. By using monomer 708 for other similar acetylenederivatives, polymers 880-884 can be prepared, as shown in FIG. 18.Polymerization is effected by the addition of a coupling region, such asPd(dppf)₂Cl₂, for polymer 880 and Pd(PPh₃)₄, for polymers 881-884. Suchselectivity is surprising considering that the vapor pressure of DNT isabout 100 times greater than that of TNT. Specific detection of TNTprovides the capability to detect explosive devices in the gaseousphase. Examples of explosive devices include land mines.

FIG. 6 shows emission spectra of polymer A in the absence and in thepresence of various analytes. In FIG. 6( a), an initial emissionspectrum 150 is obtained in the absence of an analyte. The compositionis then exposed to an analyte, dinitrotoluene (DNT) vapor, and adecrease in intensity is observed in the maxima of the spectra withtime, as denoted by curves 152 (10 s), 154 (30 s), 156 (1 min.) and 158(3 min.). FIG. 6( b) shows a detection of another example of an analyte,trinitrotoluene (TNT) vapor, by polymer A as evidenced a decrease inintensity is observed in the maxima of the spectra over time, as denotedby curves 160 (initial), 162 (10 s), 164 (30 s), 166 (1 min.) and 168(10 min.). FIG. 6( c) shows a detection of another example of ananalyte, benzoquinone vapor, by polymer A as evidenced by a decrease inintensity is observed in the maxima of the spectra over time, as denotedby curves 170 (initial), 172 (10 s), 174 (30 s), 176 (1 min.) and 178(10 min.). FIG. 6( d) shows detection of DNT, by polymer B as evidencedby a decrease in intensity is observed in the maxima of the spectra overtime, as denoted by curves 180 (initial), 182 (10 s), 184 (30 s), 186 (1min.) and 188 (10 min.). FIG. 6( e) shows a detection of TNT by polymerA as evidenced by a decrease in intensity is observed in the maxima ofthe spectra over time, as denoted by curves 190 (initial), 192 (10 s),194 (30 s), 196 (1 min.) and 198 (10 min.). The inset of FIG. 6( e)shows a plot of percent quenching versus time.

FIG. 15 shows a variety of polymers, A-D, that are capable of detectingthe presence of TNT vapor. A concentration of the vapor can be much lessthan about 1 ppb. As shown in FIG. 15, by varying the polymer type,enhanced emission intensities can be achieved and responsiveness can beoptimized. For example, polymer type A shows the fastest response time,as indicated by a plateau achieved at a time of less than about 30seconds.

FIG. 16 shows a variation in fluorescence intensities for an“all-iptycene” polymer. The all-iptycene structure provides the polymerwith excellent solubility and stability. The all-iptycene polymer issensitive to TNT detection, and increased detection times providedecreased intensities. Curve 938 corresponds to a detection time of 480s, curve 936 corresponds to a time of 120 s, curve 934 corresponds to atime of 60 s, curve 932 corresponds to a time of 30 s, and curve 930corresponds to a time of 0 s.

Polymers having hydrogen-bonding capabilities can also be synthesized.Thus, in one embodiment, the invention provides the ability to detectanalytes capable of hydrogen-bonding interactions. FIG. 19 showspolymers 680-682 that can provide hydrogen-bonding interactions as wellas charge-transfer interactions. Lewis and Bronsted base/acid sites canbe used to impart selectivity for specific analytes.

Typically, electron poor polymers can enable quenching by electron-richanalytes and thus, in one embodiment, sensors having specificity forelectron-rich analytes are provided. Thus, sensitivity to electron-richanalytes can be achieved by substituting a polymer with groups thatincrease electron affinity. FIG. 20 shows examples of electron poorpolymers 720-725, where electron poor characteristics can be conveyed bygroups such as fluoride and cyano groups. FIG. 21 shows an example of apolymer having fluoride groups. This polymer shows that fluorine isparticularly effective at producing a polymer that is not readilyquenched by TNT. This effect is likely due to the diminished reducingability of the polymer. As shown in the blot, varying the ejection timefrom 0 s to 600 s shows very little difference in fluorescenceintensities for TNT. Thus, these polymers can function as sensoryelements for hydroquinones and other electron-rich aromatics that are ofbiological or environmental importance. Examples include dioxin,dopamine, aniline, benzene, toluene and phenols.

Another aspect of the invention provides a field-effect transistor. Oneembodiment of a field effect transistor is depicted in FIG. 7. Thefield-effect transistor 200 includes an insulating medium 202 having afirst side 203 and an opposing second side 205. A polymeric article 201is positioned adjacent the first side 203 of the insulating medium.Preferably the polymeric article has a composition in accordance withthose of the invention as defined previously. A first electrode 204 iselectrically connected to a first portion of the polymeric article 201and a second electrode 206 is electrically connected to a second portionof the polymeric article 201. Each electrode 204 and 206 is positionedon the first side 203 of the insulating medium 202. The first electrode204 is further connected to the second electrode 206 by an electricalcircuit 208 external of the polymeric structure. A gate electrode 212 ispositioned on the second side 205 of the insulating medium 202 in aregion directly below the polymeric structure. The gate electrode 212 isfurther connected to a voltage source 210. A source of electromagneticradiation 216 is positioned to apply the electromagnetic radiation tothe article. The gate electrode 212 can be supported by a layer 214 suchas SiO₂ or Si. At least one species, shown as 218, is associated withthe article. Exposing the polymeric article to the electromagneticradiation, results in species 218 being a component of an excited statestructure.

Thus, the polymeric article achieves an excited state structure whichcan accept or donate charge to the species 218 associated with thearticle. The article also functions to carry the charge 220 to a regionbetween the first and second electrode. In one embodiment, the first andsecond electrode is a source and drain electrode respectively. In thisembodiment, the article injects charge 220 and changes the currentbetween the source and drain electrodes. Prior to exposing the polymericarticle to electromagnetic radiation, a current between the source anddrain electrodes is a first current. After exposing the polymericarticle to electromagnetic radiation, the current between the source anddrain electrodes is a second current. Preferably the second current isgreater than the first current.

Another embodiment provides an improvement over the first embodimentwhere the field-effect transistor further comprises a polymeric articlewhich effectively transports charge. The polymers of the invention areeffective for achieving high luminescent yields and functioning as acharge-injection polymer. In this embodiment, the field-effecttransistor has an insulating medium having a first side and an opposingsecond side. A first polymeric article is positioned adjacent the firstside of the insulating medium. Preferably this first polymeric articleis a charge-conducting polymer and can be selected from the groupconsisting of polythiophene, polypyrrole, polyacetylene, polyphenyleneand polyaniline. In another embodiment, the first polymeric article canbe any polymer of the invention described previously. First and secondelectrodes are connected to first and second portions of the firstpolymeric article respectively. Each electrode is positioned on thefirst side of the insulating medium. The first electrode is furtherconnected to the second electrode by an electrical circuit external ofthe first polymeric article. A gate electrode is positioned on thesecond side of the insulating medium below the first polymeric article,the gate electrode being connected to a voltage source. The inventioncomprises a second polymeric article positioned adjacent the firstpolymeric article. The second polymeric article is preferably acharge-injecting polymer having a composition in accordance with thoseof the invention as described previously. The field-effect transistorfurther includes a source of electromagnetic radiation applicable to asecond polymeric article. At least one species is associated with thesecond polymeric article. The at least one species, which upon exposingthe polymeric article to the electromagnetic radiation, is a componentof an excited state structure.

Another aspect of the present invention provides a sensor comprising anarticle including at least one layer including a polymeric composition.The polymeric composition includes a reporter chromophore and thearticle further comprises an activation site wherein the reporterchromophore is capable of activation by an analyte at the activationsite. An energy migration pathway within the polymeric compositionallows energy to be transferred from the pathway to the activation site.Referring back to FIG. 1, polymer 551 can have reporter chromophores 552positioned on the polymer. Chromophores 552 can also be dispersed withina bulk of the polymer 551. Excitation energy traversing throughmigration pathway 550 can transfer between various energy states ofcontinually decreasing HOMO-LUMO gap. If chromophore 552 has a HOMO-LUMOgap greater than a HOMO-LUMO gap of at least a portion of the energymigration pathway and more preferably greater than a substantial portionof the energy migration pathway, energy transfer between the pathway 550and chromophore 552 does not occur and only polymer emission 554results.

If, however, the chromophore 552 is activated by an analyte, reporterchromophore 556 can result, where a HOMO-LUMO gap is less than aHOMO-LUMO gap of at least a portion of the energy migration pathway 550and more preferably less than that of a substantial portion of energymigration pathway 550. By this arrangement, energy transfer can occurbetween polymer 551 and activated chromophore 556 to cause chromophoreemission 558.

“Activation” by an analyte results in a reporter chromophore having alower energy resulting in a decrease in the HOMO-LUMO gap. In oneembodiment, activation by an analyte results in a chromophore having asmaller HOMO-LUMO gap than that of at least a portion of the migrationpathway and preferably smaller than a substantial portion of themigration pathway. Activation can also be caused when an analyteinteracts or reacts with a partner, and the combination of analyte andpartner is capable of activating the chromophore.

An example of a sensor that has the arrangement as shown in FIG. 1 is asensor having a polymer of a first color. Upon activation, thechromophore can have a lower energy (red-shifted) that allows optimalenergy transfer from the polymer. The activated chromophores exhibit asecond color and the films have the appearance of the second color.Thus, it is an advantageous feature of the present invention that thepolymer films can first amplify an emission by channeling all of theemission through a few activated luminescent species. In this way, onlya small number of reporter chromophores need to be activated to effect atotal change in an appearance of the polymer. Detection of analytes canbe visually observed by a color change of the polymer films.

In one embodiment, the invention provides a sensor that is capable ofdetecting chemical warfare agents, and particularly agents that can bedetected in a gaseous or liquid phase. In one embodiment, the sensor isspecific for chemical warfare agents and insecticides having reactivephosphate ester groups. An example of a chemical warfare agent that canbe detected according to the invention is sarin and an example of aninsecticide is parathion.

FIG. 22 shows an example of groups that are reactive with phosphateester groups found in chemical warfare agents and insecticides. Group1130, upon reaction with a phosphate ester group 1132 results incyclization to form group 1134. Typically, reporter chromophores groups1130 have higher energy absorptions and are less emissive than reporterchromophores having group 1134. In the transformation from a lessemissive to a more emissive group, the band gap changes from high tolow. A specific example of group 1130 is group 1136 which undergoescyclization upon reaction with phosphate ester groups throughintermediate 1138 to produce the cyclized compound 1140. X can be Cl, F,or CN or other electron-withdrawing substituents; Y can be hydrogen orSiR₃; and Y₁ and Y₂ can be conjugated groups such as aromatic rings.Other examples of groups that are sensitive to phosphate esters areshown as groups 1142-1146, where Y can be hydrogen, an alkyl group or analkoxy group, preferably methyl and methoxy and hydrogen. Y can also beSiR₃, which can provide selectivity to agents having X=fluorine.

In one embodiment, the article comprises a first layer of a firstpolymer and a second layer of a second polymer, the first layer beingpositioned adjacent a second layer. A chromophore is present in thefirst and second layers. An energy migration pathway is continuousthrough the first and second layers. This arrangement is similar toplacing amplifiers in series. If an emission is initiated in one polymerand collected from another polymer, then a net amplification is theproduct of the amplification contributed by each of the two differentpolymers. FIG. 11A shows emission 950 at a first energy for a firstpolymer 951 and emission 952 at a second energy for a second polymer953. Article 955 schematically shows polymers 951 and 953 placed inseries, i.e. as a double layer, and energy can migrate along pathway 958to provide amplified emission 954, which is a product of the emissionsof polymers 951 and 953 (i.e. emission 950 times emission 952). FIG. 11Bshows article 961 having a multi-layer, wherein energy migrates alongpathway 962 resulting in enhanced emission 956 which is a product of theemission of each individual polymer. FIG. 12 shows a demonstration ofenhanced sensitivity of a sensor for TNT. Polymer 532 is a donor polymerthat exhibits a dominant absorbance at 430 nm and polymer 530 is anacceptor polymer having a dominant absorbance at 490 nm. Polymers 530and 532 are placed in series. By exposing the double layer to a 490 nmexcitation (specific for acceptor polymer 530), curve 536 is obtained.By exposing the resulting double layer to a 430 nm excitation (specificfor donor polymer 532), energy can be amplified by traveling from ahigher energy polymer to a lower energy polymer, and this amplificationis demonstrated by the enhanced intensity curve 534. FIG. 13 shows aschematic of a multi-layer sensor 1010, having a gradient of energy bandgaps as indicated by arrows 1012. Activated reporter chromophore 1011emits enhanced intensity 1013.

The band gaps of the polymers can be tailored by varying the molecularstructure and providing different substituted groups on the polymers.FIG. 14 shows a transporter chromophore A and a variety of polymers B-Fand their resulting emissions. From FIG. 14, this class of polymersshows a range of emissions from approximately 380 nm to approximately560 nm.

The polymer can be a homo-polymer or a co-polymer such as a randomco-polymer or a block co-polymer. In one embodiment, the polymer is ablock co-polymer. An advantageous feature of block co-polymers is thatthe effect of a multi-layer can be mimicked. Each block will havedifferent band gap components and by nature of the chemical structure ofa block co-polymer, each gap component is segregated. Thus, amplifiedemissions can be achieved with block co-polymers. Thus, a broad scope ofstructures can be produced. Band gaps, amplifications and selectivitiesfor analytes can be achieved by modification or incorporation ofdifferent polymer types. The polymer compositions can vary continuouslyto give a tapered block structure and the polymers can be synthesized byeither step growth or chain growth methods.

Another aspect of the invention provides methods for the determinationof analytes which may have weak electrostatic interactions with and/ordo not otherwise readily interact with conjugated polymers. For example,many of these analytes may be poor electron acceptors (e.g., haveunfavorable reduction potentials) and may not readily interact withconjugated polymers via a charge transfer reaction, such as aphoto-induced charge transfer reaction. In some embodiments, sensors andmethods of the invention may facilitate (e.g., enhance, accelerate,etc.) charge transfer reactions between an analyte and a luminescentpolymer. Examples of such analytes include, but are not limited to,those typically incorporated into plastic explosives formulations aswell as a number of toxic industrial chemicals, various common organicsolvents, and pesticide residues.

Accordingly, some embodiments of the invention provide sensorscomprising luminescent polymers comprising a hydrogen-bond donor thatcan facilitate (e.g., enhance) interaction between a luminescent polymerand an analyte. The hydrogen-bond donor can interact with the analyte toform a complex between the hydrogen-bond donor and the analyte, and thecomplex may be capable of interacting with the luminescent polymer,whereas, in the absence of the hydrogen-bond donor, the analyte would beless capable of interacting with the luminescent polymer. In some cases,in the absence of the hydrogen-bond donor, the analyte would not becapable of interacting with the luminescent polymer. The complex mayalso be capable of causing the luminescent polymer to signal thepresence of the analyte.

As used herein, the term “complex” refers to a species formed by theintermolecular association between at least two chemical moieties (e.g.,between a hydrogen-bond donor and an analyte), wherein the associationdoes not necessarily comprise formation of a covalent bond, but cancomprise the formation of other types of bonds, including ionic bonds,hydrogen bonds (e.g., between hydroxyl, amine, carboxyl, thiol and/orsimilar functional groups, for example), dative bonds (e.g. complexationor chelation between metal ions and monodentate or multidentateligands), or the like, and/or other types of interactions betweenchemical moieties wherein electrons are shared. In some embodiments, thehydrogen-bond donor may form a hydrogen bond with the analyte to formthe complex. In some cases, the complex may be a charge transfer complexformed between the hydrogen-bond donor and the analyte.

Formation of the complex may cause a change in the properties of atleast one of the chemical components of the complex. For example, thecomplex may comprise the hydrogen-bond donor and the analyte, whereinthe properties of at least one or both of the hydrogen-bond donor andthe analyte are changed. In one embodiment, the interaction between thehydrogen-bond donor and the analyte, i.e., to form the complex, maycomprise a change in a property of the analyte. For example, the analytemay have a first reduction potential and, upon interaction with thehydrogen-bond donor to form the complex, the analyte may have a secondreduction potential, wherein the second reduction potential may increasethe ability of the analyte to interact with the luminescent polymer via,for example, a charge transfer reaction. In some embodiments, formationof the complex may cause an analyte to be brought or held in closerproximity to the luminescent polymer, thereby increasing the ability ofthe analyte to interact with the luminescent polymer.

In some embodiments, the ability of an analyte to interact with aluminescent polymer may depend on the relative reduction potentials ofthe analyte and the luminescent polymer. For example, in some cases, ananalyte may act as a quencher for a luminescent polymer (e.g.,“turn-off” mechanism) if the analyte has a LUMO which is lower in energy(e.g., low reduction potential ) relative to the conduction band of theluminescent polymer, allowing the polymer, in the excited-state, totransfer electrons in the conduction band to the LUMO of the analyte.That is, the excited-state luminescent polymer may be quenched by theanalyte via electron transfer. In contrast, an analyte having a LUMOwhich is higher in energy (e.g., high reduction potential) relative tothe conduction band of the luminescent polymer, the polymer, in theexcited-state, may be unable to transfer electrons in the conductionband to the LUMO of the analyte. The reduction potential of theluminescent polymer may depend on, for example, the ionization potentialand/or band gap of the polymer. In some cases, the analyte has areduction potential which is made less negative (e.g., lowered) upon itsinteraction with a hydrogen-bond donor, such that the analyte may morereadily interact with the luminescent polymer. That is, thehydrogen-bond donor may “activate” the analyte towards interaction withthe luminescent polymer. Such interactions may enhance the response ofthe luminescent polymer to the analyte.

The hydrogen-bond donor may be associated with (e.g., bonded to) theluminescent polymer by various means, such as covalent bonds, ionicbonds, hydrogen bonds, dative bonds, or the like. In one embodiment, thehydrogen-bond donor is covalently bonded to the luminescent polymer.

Those of ordinary skill in the art would be able to identifyhydrogen-bond donors suitable for use in the present invention. Forexample, hydrogen-bond donors may comprise an electron-poor group, suchas fluorine, nitro, acyl, cyano, sulfonate, or the like, and optionallyat least one hydrogen (e.g., acidic hydrogen) adjacent to theelectron-poor group that may form a hydrogen-bond with an analyte toform the complex. Examples of hydrogen-bond donors include fluorinatedalcohols, such as hexafluoroisopropanol.

In some embodiments, the hydrogen-bond donor may be chiral, such thatthe hydrogen-bond donor may selectively interact with a particularstereoisomer of an analyte.

Luminescent polymers comprising hydrogen-bond donors may be synthesizedaccording to methods known in the art and as described herein. In anillustrative embodiment, FIG. 34 shows a schematic synthesis of amonomer having a hexafluoroisopropanol group and FIG. 35 shows aschematic synthesis of a monomer having two hexafluoroisopropanolgroups. The polymerization of such monomers is shown in FIG. 36.

Examples of analytes which may interact with hydrogen-bond donors asdescribed herein include, but are not limited to, heterocycles (e.g.,nitrogen heterocycles), other nitrogen-containing compounds, such ascompounds comprising nitro, nitrate, and/or nitrite groups. In someembodiments, the analyte comprises a heterocycle comprising nitrogen.Some specific examples of analytes may include 2,4-dinitrotoluene,2,4,6-trinitrotoluene, 4-aminopyridine, N,N′-dimethylamino-pyridine,pyridine, or 2,4-dichloro-pyrimidine.

The terms “heterocyclyl” and “heterocyclic group” are recognized in theart and refer to 3- to about 10-membered ring structures, such as 3- toabout 7-membered rings, whose ring structures include one to fourheteroatoms. Examples of heterocyclyl groups include, for example,thiophene, thianthrene, furan, pyran, isobenzofuran, chromene, xanthene,phenoxathin, pyrrole, imidazole, pyrazole, isothiazole, isoxazole,pyridine, pyrazine, pyrimidine, pyridazine, indolizine, isoindole,indole, indazole, purine, quinolizine, isoquinoline, quinoline,phthalazine, naphthyridine, quinoxaline, quinazoline, cinnoline,pteridine, carbazole, carboline, phenanthridine, acridine, pyrimidine,phenanthroline, phenazine, phenarsazine, phenothiazine, furazan,phenoxazine, pyrrolidine, oxolane, thiolane, oxazole, piperidine,piperazine, morpholine, lactones, lactams such as azetidinones andpyrrolidinones, sultams, sultones, and the like. The heterocyclic ringmay be substituted at one or more positions with such substituents asdescribed above, as for example, halogen, alkyl, aralkyl, alkenyl,alkynyl, cycloalkyl, hydroxyl, amino, nitro, sulfhydryl, imino, amido,phosphonate, phosphinate, carbonyl, carboxyl, silyl, ether, alkylthio,sulfonyl, ketone, aldehyde, ester, a heterocyclyl, an aromatic orheteroaromatic moiety, CF₃, CN, or the like.

In some embodiments, sensors for analytes as described herein maycomprise a luminescent polymer having the structure,

wherein R²⁷ and R²⁸ are independently alkyl, heteroalkyl, aryl,heteroaryl, or substituted derivatives thereof, and n is at least 1 Insome cases, n is at least 10, at least 100, at least 500, at least 1000,or at least 5000. In some embodiments, at least one of R²⁷ and R²⁸comprises the structure,

wherein m is at least 1. In some embodiments, at least one of R²⁷ andR²⁸ has the structure,

In some embodiments, the luminescent polymer is a polyarylene,polyarylene vinylene, polyarylene ethynylene, ladder polymer, orsubstituted derivative thereof.

Another aspect of the present invention provides a polymer capable ofemission, wherein the emission is variable and sensitive to a dielectricconstant of a surrounding medium. FIG. 24 shows an example of a polymersubstituted with fluorinated alcohol groups (e.g., HFIP) for hydrogenbonding with weak hydrogen bonded acceptors such as nitro groups.Chromophores having such fluorinated alcohol groups can experience anemission sensitive to dielectric constants and can be used to detect thebinding of high explosives such as RDX(hexahydro-1,3,5-trinitro-1,3,5-triaxine), PETN(2,2-bis[(nitrooxy)-methyl]-1,3-propanediol dinitrate (ester)) and othernitro-containing species.

Another aspect of the present invention provides a sensor having areporter chromophore capable of emission, wherein the emission isvariable and sensitive to an electric field of a medium surrounding thechromophore. Selective matching of energies involved in the energymigration pathway to a vast array of the activated and unactivatedchromophores, as described above, can produce enhanced emissions.

Another embodiment of the present invention provides a formation ofexcimer and exciplex structures which will provide lower energychromophores having an emission intensity that can be enhanced by energymigration. Exciplex structures can be used as a detector for cations.Referring to FIG. 25, a polymer can include a group that is capable ofbinding a cation, such as a crown ether. Cation bonding is enhanced whentwo crown ethers are used for binding. This arrangement results inincreased interaction between the polymer backbones and possiblyπ-stacking interactions can occur. FIG. 25 shows a fluorescence spectraof a crown ether containing polymer before and after addition ofpotassium salts. A new band (indicated by the upward arrow) is theresult of an excimer induced by potassium ions. Crown ethers of varioussizes, as is well known in the art, can be used to selectively bindcations of different sizes. FIG. 26 shows a schematic for the synthesisof a polymer containing a crown ether, and FIG. 27 shows polymers450-453 that incorporate groups capable of binding cations. Othermechanisms for the formation of exciplexes include the binding ofaromatic analytes.

The function and advantage of these and other embodiments of the presentinvention will be more fuilly understood from the examples below. Thefollowing examples are intended to illustrate the benefits of thepresent invention, but do not exemplify the full scope of the invention.

EXAMPLE 1 Synthesis of Poly(phenyleneethynylene)s Linked to PolystyreneResin Beads

All manipulations were performed under a nitrogen atmosphere usingstandard Schlenk techniques or a Inovative Technologies dry box.Tetrahydrofuran was distilled from sodium benzophenone under nitrogen.Toluene and diisopropylamine were distilled from sodium under nitrogenand then degassed. NMR spectra were recorded on a Varian VXR-500spectrometer at 500 (¹H), 125 (¹³C) MHz using CDCl₃ as solvent. Thechemical shifts are reported in ppm relative to TMS. Infrared spectrawere collected as Nujol mulls on a Mattson Galaxy 3000 spectrometer,using KBr cells. Elemental analyses were performed by Desert Analytics.The molecular weights of polymers were determined using a HewlettPackard series 1100 HPLC instrument equipped with a Plgel 5 mm Mixed-C(300×7.5 mm) column and a diode array detector at 245 nm at a flow rateof 1.0 mL/min in THF. The molecular weights were calibrated relative topolystyrene standards purchased from Polysciences, Inc. Polymer thinfilms were spin cast onto 18×18 mm glass slides. UV-vis spectra wereobtained using a Hewlett Packard 8452A diode array spectrophotometer.Fluorescence experiments were performed using a SPEX Fluorolog-t2fluorometer (model FL 112, 450W xenon lamp) equipped with a model 1935Bpolarization kit. Polymer thin-film spectra were recorded by front face(22.5°) detection. Time decay of fluorescence was determined by aphase-modulation method, using frequencies between 10 and 310 MHz. Thecompounds were purchased from Aldrich.

The synthesis of a polymer in accordance with the invention is detailedhere. Starting materials diisopropylamine (DIPA) and toluene weredistilled from sodium. The compounds 4-iodobenzoic acid,N,N-dimethylaminopyridine (DMAP), diisopropylcarbodiimide (DIC),Pd(PPh₃)₄, and CuI were purchased from Aldrich. The compounds2,5-diethynyl-4-decyloxyanisole (10) and1,4-dihexadecyloxy-2,5-diiodobenzene (20) were prepared according toliterature procedures. The pentiptycene monomer (S) was prepared asoutlined in Example 2. Aminomethylated polystyrene resin (200-400 mesh,1.00 mmol/g) and Wang resin (200-400 mesh, 0.96 mmol/g) were purchasedfrom Nova Biochem.

Preparation of 4-Iodo-Benzoic Acid Ethyl Ester. (40) A mixture of4-iodobenzoic acid (10.0 g, 40.3 mmol), ethanol (100 mL) andconcentrated H₂SO₄ (10 mL) was heated at reflux for 16 h. After cooling,excess solvent was removed from the reaction mixture under reducedpressure. The remaining oil was poured over ice (100 g) and the mixturewas neutralized with a saturated solution of NaHCO₃. This mixture wasextracted with hexane (200 mL). The hexane solution was washed withwater (2×50 mL), dried over MgSO₄, and concentrated under reducedpressure. The remaining oil was distilled (110° C., 0.02 mm Hg) to give10.06 g of the product as a colorless oil in 90% yield. ¹H NMR spectraand IR spectra are consistent with those reported in the literature.

Phenyliodide Functionalized Wang Resin. (E) Wang resin (0.200 g),4-iodobenzoic acid (0.0952 g, 0.384 mmol), and DMAP (0.0235 g, 0.192mmol) were placed in a 100 mL reaction vessel. The vessel was evacuatedand refilled with Ar three times. Then, DMF (15 mL) was added followedby DIC (75 mL, 0.48 mmol) and the resulting mixture was shaken for 48 h.The solution was removed by filtration and the resin was washed with DMF(3×20 mL) and CH₂Cl₂ (3×20 mL). The resin was then dried under vacuum at60° C. for 3 h.

Polymerization of Poly(phenyleneethynylene) on PhenyliodideFunctionalized Resin. (F) A schematic of the polymerization is shown inFIG. 8( a). A 100 mL reaction vessel was charged with the phenyliodidefunctionalized Wang resin (0.050 g), 10 (0.055 g, 0.176 mmol), and 20(0.159 g, 0.176 mmol). The flask was evacuated and refilled with Arthree times. In a dry box Pd(PPh₃)₄ (6.8 mg, 0.0059 mmol) and CuI (2.2mg, 0.012 mmol) were added to the flask. DIPA (1.0 mL) followed bytoluene (2.5 mL) were added to the reaction mixture. The solutionrapidly became fluorescent yellow. The reaction mixture was heated at60° C. for 16 h. The solution was then removed by filtration and theresin was washed with toluene (3×20 mL) and CHCl₃ (3×20 mL). The finalwashings were colorless. The highly fluorescent yellow resin beads werethen dried under vacuum at 60° C. for 3 h. Emission (solid film, λ, nm):485, 515.

The polymer that was rinsed away from the resin beads was precipitatedinto acetone (300 mL) and washed with methanol and hexane. UV-Vis(CHCl₃, λ, nm): 319, 454. Emission (CHCl₃, λ, nm): 477, 504.

Polymerization of Pentiptycene-derived Poly(phenyleneethynylene) onPhenyliodide Functionalized Resin. (G) A 100 mL reaction vessel wascharged with the phenyliodide functionalized Wang resin (0.050 g), S(0.053 g, 0.111 mmol), and 20 (0.100 g, 0.123 mmol). The flask wasevacuated and refilled with Ar three times. In a dry box Pd(PPh₃)₄ (4mg, 0.004 mmol) and CuI (1 mg, 0.007 mmol) were added to the flask. DIPA(1.0 mL) followed by toluene (2.5 mL) were added to the reactionmixture. The reaction mixture was heated at 60° C. for 48 h. Thesolution was then removed by filtration and the resin was washed withtoluene (3×20 mL) and CHCl₃ (3×20 mL). The final washings werecolorless. The highly fluorescent yellow resin beads were then driedunder vacuum at 60° C. for 3 h. Emission (solid film, λ, nm): 456, 479.

Ethyl Ester End Functionalized Poly(phenyleneethynylene). (H) Aschematic of the polymerization is shown in FIG. 8( b). A 25 mL Schlenkflask was charged with 10 (0.180 g, 0.222 mmol), 20 (0.076 g, 0.24mmol), and 40 (0.0123 g; 0.044 mmol). The flask was purged with Ar andthen charged with Pd(PPh₃)₄ (13 mg, 0.011 mmol) and CuI (2.1 mg, 0.011mmol). DIPA (1.0 mL) and toluene (2.5 mL) were added and the reactionmixture was heated at 60° C. for 14 h. The reaction mixture was addeddropwise to vigorously stirred acetone (200 mL). The polymer wascollected on a filter and washed with acetone, methanol, and hexaneuntil the filtrate was no longer colored. The polymer was then driedunder vacuum at 60° C. for 3 h to afford H (0.16 g) in 78% yield. UV-Vis(CHCl₃, λ, nm): 319, 452. Emission (CHCl₃, λ, nm): 476, 504.

Ethyl Ester End Functionalized Pentiptycene-derivedpoly(phenyleneethynylene). (I) A 25 mL Schlenk flask was charged with 30(0.080 g, 0.167 mmol), 20 (0.123 g, 0.152 mmol), and 40 (0.0084 g; 0.030mmol). The flask was purged with Ar and then charged with Pd(PPh₃)₄ (9mg, 0.008 mmol) and CuI (1.4 mg, 0.008 mmol). DIPA (1.0 mL) and toluene(2.5 mL) were added and the reaction mixture was heated at 70° C. for 48h. The reaction mixture was added dropwise to vigorously stirred acetone(300 mL). The polymer was collected on a filter and washed with acetone,methanol, and hexane until the filtrate was no longer colored. Thepolymer was then dried under vacuum at 60° C. for 3 h to afford I (0.14g) in 83% yield. UV-Vis (CHCl₃, λ, nm): 336, 426. Emission (CHCl₃, λ,nm): 454, 482.

End Functionalized poly(phenyleneethynylene) (H) grafted ontoaminomethylated polystyrene resin. (J). A schematic of this synthesis isshown in FIG. 8( b) A 25 mL flask was charged with aminomethylatedpolystyrene resin (0.050 g; 0.050 mmol), end functionalizedpoly(phenyleneethynylene) (H) (0.030 g), sodium methoxide (3.0 mg; 0.055mmol), and toluene (7.0 mL). This mixture was heated at reflux for 24 h.The solution was then removed by filtration and the resin was washedwith toluene (3×20 mL) and CHCl₃ (3×20 mL). The final washings werecolorless. The highly fluorescent yellow resin beads were then driedunder vacuum at 60° C. for 3 h. Emission (solid film, λ, nm): 462, 500.

End Functionalized Pentiptycene-derived poly(phenyleneethynylene) (I)grafted onto aminomethylated polystyrene resin. (K). A 25 mL flask wascharged with aminomethylated polystyrene resin (0.050 g; 0.050 mmol),end functionalized poly(phenyleneethynylene) (I) (0.030 g), sodiummethoxide (3.0 mg; 0.055 mmol), and toluene (7.0 mL). This mixture washeated to 110° C. for 24 h. The solution was then removed by filtrationand the resin was washed with toluene (3×20 mL) and CHCl₃ (3×20 mL). Thefinal washings were colorless. The highly fluorescent yellow resin beadswere then dried under vacuum at 60° C. for 3 h.

EXAMPLE 2 Synthesis of Monomers and Polymer A, B and C

Syntheses of polymer A and B are outlined in FIG. 9( a) and thesynthesis of polymer C is shown in FIG. 9( b).

General. All chemicals were of reagent grade. Benzoquinone wasrecrystallized in hexane before use. Anhydrous toluene and THF werepurchased from Aldrich Chemical Co. Inc. NMR (¹H and ¹³C) spectra wererecorded on Bruker AC-250, Varian Unity-300, or Varian VXR-500Spectrometers, and chemical shifts are reported in ppm relative to TMSin proton spectra and to CHCl₃ in carbon spectra. UV-vis spectra wereobtained from a Hewlett-Packard 8452A diode array spectrophotometer.Fluorescence studies were conducted with a SPEX Fluorolog-3 fluorometer.

Compounds L and M. To a mixture of anthracene (17.8 g, 0.1 mol) andbenzoquinone (5.4 g, 0.05 mol) in a 200 mL round-bottom flask fittedwith a condenser was added 75 mL of mesitylene. The mixture was refluxedfor 24 h and then the solid was filtered after cooling to roomtemperature. The hydroquinone solid was digested in 100 mL of hot xylenetwice and filtered (16.5 g). The crude hydroquinones (8 g) weredissolved in hot glacial acetic acid (ca 300 mL) and then a solution of1.5 g of potassium bromate (9 mmol) in 100 mL of hot water was added. Adeep orange color and precipitate developed immediately. The solutionwas boiled for a few minutes and then an additional 100 mL of hot waterwas added and the heat was removed. The orange quinone solid wascollected after the solution was cooled. The quinones were washed withacetic acid and then with water. The crude quinones were dissolved inchloroform (ca. 120 mL) and washed with sodium bicarbonate and brine.The organic layer was separated and dried (MgSO₄). The dark-coloredimpurities were removed by filtering the chloroform solution through athin layer of silica gel. The resulting orange solution was adsorbedonto ca. 50 g of silica gel. The resulting yellow silica gel solidmixture was chromatographed using hexane/ethyl acetate (5:1) as theeluent to obtain 80-95% pure of compound L, which can be furtherpurified by column chromatography using pure chloroform as the eluent.Compound M stays with silica gel and was obtained with 97-100% pure byre-dissolving the silica gel solid mixture in chloroform and then theremoval of silica gel and chloroform solvent. The overall yields for Land M were 13% and 39%, respectively. Compound L: (mp=294.0° C.,lit=292-296° C.).

Compounds N, O, and P. A mixture of pentacene (0.96 g, 3.45 mmol) andquinone (1.27 g, 4.49 mmol) in 3 mL of toluene was refluxed for 3 daysand then cooled. The resulting yellow solid (1.87 g) was filtered andwashed with hexane. The solid was placed in a round-bottom flask and ca.80 mL of glacial acetic acid was added and then the solution was heatedto reflux and then 5-10 drops of HBr (48%) was added. The color ofsolution faded in a short period of time. The solution was cooled after30 min and then any undissolved solid was filtered off. The filtrate wasthen reheated again and potassium bromate (0.3 g in 20 mL hot water) wasadded. The solution was boiled for a few minutes and then 10 mL more ofhot water was added and the heat was removed. The orange quinone solidwas collected and washed with acetic acid and water. Columnchromatography using pure chloroform as eluent allowed the separation ofP from the mixture of N and O, which can be separated by another columnchromatography using a mixed solvent of chloroform and hexane (2:1).

Compounds Q and R. A general procedure is illustrated by the synthesisof Q. Under an atmosphere of argon, one equivalent of n-butyllithium(2.5 mmol) in hexane was added dropwise to a solution of(trimethylsilyl)acetylene (0.35 mL, 2.5 mmol) in THF at 0° C. Themixture was then kept at 0° C. for another 40 min before it wastransferred to a solution of quinone M (0.46 g, 1 mmol) in THF at 0° C.The mixture was warmed up to room temperature and stirred overnight. Thereaction was quenched with 1 mL of 10% HCl and then subjected to aCHCl₃/H₂O workup. The solvent was removed and hexane was then added tothe residue. The resulting white solid (0.59 g, 90%, 0.90 mmol), whichis a mixture of the trans and cis isomers, was collected by filtration.This crude solid was dissolved in 10 mL acetone and then a solution oftin(II)chloride dihydrate (0.51 g, 2.25 mmol) in 50% of acetic acid (10mL) was added dropwise. This mixture was stirred at room temperature foranother 24 h and the resulting solid product was filtered. The solid wasthen dissolved in CHCl₃ and washed with water, sodium bicarbonate andthen dried (MgSO₄). The CHCl₃ was removed in vacuo and the residue waswashed with hexane to remove the yellow impurities. The resulting whitesolid was collected (yield 85%).

Compounds S and T. The deprotection of trimethylsilyl group was carriedout by dissolving compounds Q or R in a mixture of KOH (two tablets in 1mL H2O), THF, and MeOH and stirring at room temperature for 5 h. Theresulting solid product was filtered and washed with water and thendried in vacuo.

Polymers A, B, and C. A general procedure is illustrated by thesynthesis of polymer A. Under an atmosphere of argon,diisopropylamine/toluene (2:3, 2.5 mL) solvent was added to a 25 mLSchlenk flask containing compound S (40 mg, 0.084 mmol),1,4-bis(tetradecanyloxyl)-2,5-diiodobenzene (63 mg, 0.084 mmol), CuI (10mg, 0.053 mmol), and Pd(Ph₃)₄ (10 mg, 0.0086 mmol). This mixture washeated at 65° C. for three days and then subjected to a CHCl₃/H₂Oworkup. The combined organic phase was washed with NH₄Cl, water and thendried (MgSO₄). The solvent was removed in vacuo, and the residue wasreprecipitate in methanol three times. The polymer was a yellow solid(76 mg, 75%).

EXAMPLE 3 Synthesis of the Monomer 1,4-Dinaphthyl-2,5-diacetylidebenzene(DD)

An overall scheme is depicted in FIG. 10( b).

1,4-Dibromo-2,5-dinaphthylbenzene (AA). Adapted from literatureprocedure reported by M. Goldfinger et al. A 100 ml Schlenk flask wascharged with 1,4-dibromo-2,5-diiodobenzene (0.93 g, 1.91 mmol),naphthalene boronic acid (0.72 g, 4.19 mmol), triphenylphosphine (0.075g, 0.29 mmol), palladium tetrakistriphenylphosphine (0.022 g, 0.019mmol), and KOH (2.2 g, 39 mmol). To this mixture, 5 mL deionized H₂O and20 mL nitrobenzene were introduced via syringes. The resulting mixturewas initially purged with a rapid stream of Argon, then was evacuatedand refilled with argon five times before it was heated to 90° C. in anoil bath. After maintaining at this temperature for 24 hrs, the solventwas removed by distillation under high vacuum. The residue wastransferred into a filtration funnel and successively washed with 100 mLH₂O, 20 mL acetone and 20 mL cold chloroform. Drying of the rinsedsolids under vacuum afforded an off-white powder (0.65 g, 70%).

1,4-Diiodo-2,5-dinaphthylbenzene (BB): At −78° C., AA (0.3 g, 0.61 mmol)was poured into a Schlenk flask containing t-BuLi (3mL, 1.7 M inhexanes) and 15 mL THF. The resulting mixture was allowed to warm up to−40° C. and stirred at this temperature for 1 hr. At this temperature,I₂ (1.5 g, 5.9 mmol) crystals were added in one portion under strongargon flow. The deep red solution was stirred at room temperature forfour hours before it was quenched by adding dilute sodium hydrosulfitesolution. The solvent was removed under vacuum and the residual solidwas washed with water, acetone, and chloroform sequentially to give apale white powder (0.16 g, 50%).

1,4-Dinaphthyl-2,5-di((trimethylsilyl)ethynyl)benzene (CC): Under anargon atmosphere, BB (0.14 g, 0.24 mmol), Pd(PPh₃)₂Cl₂ (8.5 mg, 0.012mmol), and CuI (0.005 g, 0.024 mmol) were mixed in 1 mL HN(iPr)₂ and 5mL toluene. Trimethylsilylacetylene (0.071 g, 0.72 mmol) was thenintroduced into the mixture via a syringe. The resulting brown solutionwas heated to 70° C. for two hours before it was cooled down andfiltered to remove insoluble iodium salts. The filtrate wasconcentrated, loaded onto a silica gel column and eluted with themixture of hexanes and chloroform (10:1) to give a light yellow solid(0.1 g, 80%).

1,4-Dinaphthyl-2,5-diacetylidebenzene (DD): A solution of potassiumhydroxide (150 mg, 2.67 mmol) in 2 mL H₂O and 8 mL MeOH was addeddropwise to a solution of 3 in 16 mL THF under magnetic stirring. Afterthe clear solution was stirred at room temperature overnight the solventwas removed under vacuum. The residue was dissolved in CHCl₃, washedwith H₂O and concentrated. Trituration of the solid with acetone,filtration of the precipitate, and drying the product under high vacuumgave a essentially pure off-white solid (0.041 g, 54%).

EXAMPLE 4 Polymer Synthesis from Monomer DD

A schematic of this synthesis is shown in FIG. 10( a). A Schlenk flaskwas charged with DD (0.019 g, 0.049 mmol),1,4-ditetradecyloxy-2,5-diiodobenzene (0.035 g, 0.049 mmol), palladiumtetrakistriphenylphosphine (0.0056 g, 0.0048 mmol), CuI (0.001 g, 0.0053mmol), 1.5 mL toluene, and 1 mL HN(iPr)₂. The heterogeneous mixture wasinitially stirred at room temperature for 20 min then heated to 70° C.for 48 hrs. The resulting brownish fluorescent solution was precipitatedin MeOH and the polymer precipitate was isolated by suction filtration.Reprecipitation of the polymer in acetone from chloroform give a brownpolymer (0.03 g, 71%).

EXAMPLE 5 Synthesis of Triphenylene-Based Monomers

FIGS. 30 and 31 schematically show the synthesis of triphenylene-basedmonomers having acetylene polymerization units.

The compound 1,2-didecyloxybenzene (1a) was prepared according toliterature procedures.

1,2-di(2-ethylhexyloxy)benzene (1b). In a 2 L flask were combined2-ethylhexylbromide (127.9 mL, 0.719 mol), KI (21.71 g, 0.131 mol),K₂CO₃ (180.8 g, 1.31 mol), and chatechol (36.0 g, 0.327 mol). The flaskwas purged with N₂ for 10 min. and 1 L butanone was added. The mixturewas heated at reflux for 22 d. The reaction mixture was then filteredand the solids washed with ether. The filtrate was washed several timeswith water, dried (MgSO₄) and concentrated under reduced pressure. Thecrude product was distilled (80° C./0.02 mmHg) to give1,2-di(2-ethylhexyloxy)benzene (1b) as a colorless oil in 79% yield.

1,2-diethoxybenzene (1c). The synthesis of this compound was initiatedsimilarly to the synthesis of 1b. The reaction mixture was stirred atroom temperature for 2 d. The reaction mixture was then filtered and thesolids were rinsed with ether. The filtrate was washed with diluteaqueous KOH and several times with water. The organic fraction was dried(MgSO₄) and concentrated under reduced pressure. The crude product wasdistilled (80° C./5 mmHg) to give 1,2-diethoxybenzene (1c) as acolorless crystalline solid in 11% yield (mp=40.0-40.5).

4-bromo-1,2-didecyloxybenzene (2a). A CH₃CN solution (100 mL) of NBS(13,67 g, 76.80 mmol) was added dropwise to a CH₃CN solution (300 mL) of1a (30.00 g, 76.80 mmol). The mixture was stirred at reflux for 12 h inthe absence of light. The reaction mixture was cooled and the solventwas removed under reduced pressure. The residue was extracted withether, washed with a saturated NaHCO₃ solution and water. After dryingwith MgSO₄ the solvent was removed under reduced pressure.Crystallization from THF/MeOH afforded colorless crystals of4-bromo-1,2-didecyloxybenzene (2a) in 93% yield (mp 39.5-40° C.).

4-bromo-1,2-di(2-ethylhexyloxy)benzene (2b). Solid NBS (26.21 g, 0.147mol) was added to an ice cold CH₂Cl₂ solution (250 mL) of 1b under N₂ inthe absence of light. Just enough DMF was added (30 mL) to disolve theNBS. The reaction mixture was allowed to warm to room temperature andthen stirred for 12 h. The mixture was then poured into water. Theorganic layer was washed with a saturated LiCl solution and water. Afterdrying with MgSO4 the solvent was removed under reduced pressure. Theremaining oil was distilled (160° C./0.01 mmHg) to yield4-bromo-1,2-di(2-ethylhexyloxy)benzene (2b) in 96% yield as a colorlessoil.

4-bromo-1,2-diethoxybenzene (2c). Compound 4-bromo-1,2-diethoxybenzene(2c) was prepared according to the procedure for the synthesis of 2b.The crude product was distilled (75° C./0.03 mmHg) to give 2c as acolorless oil in 86% yield.

3,3′,4,4′-tetrakisdecyloxybiphenyl (3a). A hexane solution of ^(n)BuLi(1.57 M, 1.02 mL) was added dropwise to a THF solution (50 mL) of 2awhich had been precooled to −30° C. Once the addition was complete thereaction mixture was allowed to warm to room temperature. After stirringfor an additional 12 h the reaction mixture was poured into water andextracted with ether. The ether layer was washed with water and driedwith MgSO₄. The solvent was removed under reduced pressure. The residuewas crystallized from a THF/MeOH mixture at −15° C. to give colorlesscrystals of 3,3′,4,4′-tetrakisdecyloxybiphenyl (3a) in 38% yield (mp85-86° C.).

3,3′,4,4′-tetrakis(2-ethylhexyl)biphenyl (3b). A THF solution (500 mL)of 2b (46.32 g, 0.112 mol) was cooled to −60° C., and a hexane solutionof ^(n)BuLi (143 mL, 1.57 M, 0.224 mol) was added. The mixture wasallowed to warm to 0° C. over 1 h and then stir at that temperature for1 h. The solution was then cooled to −60° C. and CuCl₂ (30.12 g, 0.224mol) was added. The mixture was allowed to warm to room temperature over1 h and was then heated at reflux for 12 h. The reaction mixture wascooled to room temperature and poured into dilute HCl. This mixture wasextracted twice with ether. The combined organic fractions were washedwith water, dried with MgSO4, and filtered through a short plug ofsilica. Solvent was removed under reduced pressure and the remaining oilwas purified by column chromatography using a 2% ether/98% hexanesolvent mixture to afford 3b (RF=0.26) as a slightly yellow oil in 51%yield.

3,3′,4,4′-tetraethoxybiphenyl (3c). Compound 3c was prepared by the samemethod described for 3b using 2c as starting material. The crude productwas crystallized from THF/MeOH to afford 3c as colorless plates in 66%yield (mp=140-141° C.).

1,4-dimethoxy-6,7,10,11-tetrakis(decyloxy)triphenylene (4a). Solid 3a(5.50 g, 7.06 mmol) was added to an ice cold suspension of anhydrousFeCl₃ (9.16 g, 56.5 mmol) in dry CH₂Cl₂ (250 mL). Within 2 min1,4-dimethoxybenzene (3.90 g, 28.2 mmol) was added to the green reactionmixture. The reaction mixture was allowed to warm slowly to roomtemperature and then stir for an additional 12 h. The reaction mixturewas quenched with anhydrous MeOH (30 mL). The volume of the mixture wasreduced to 50 mL under reduced pressure and MeOH (200 mL) was added tothe resulting oil. The slightly violet product was colled on a frit andwashed with MeOH. The product was further purified by columnchromatography using a 50% CH₂Cl₂/50% hexane solvent mixture to afford4a (RF=0.24) as a colorless solid in 84% yield (mp 69-70° C.).

1,4-dimethoxy-6,7,10,11-tetrakis(2-ethylhexyloxy)triphenylene (4b). Thereaction to produce 4b was initiated as described for 4a. Afterquenching the reaction with anhydrous MeOH the volume of the mixture wasreduced under reduced pressure. The remaining mixture was poured intowater and extracter twice with ether. The ether fractions were washedwith water, dried with MgSO₄, and concentrated under reduced pressure.The remaining solid was purified by column chromatography on silica gel(1:3 CH₂Cl₂/hexane) to afford 4b as a colorless waxy solid in 28% yield(mp=54-56° C.).

1,4-dimethoxy-6,7,10,11-tetraethoxytriphenylene (4c). Compound 4c wasprepared according to the procedure for the synthesis of 4b. The productwas crystallized from THF/MeOH at −15° C. to afford colorless needles in30% yield (mp 157-157.5° C.).

6,7,10,11-tetrakis(decyloxy)triphenylene-1,4-dione (5a). An aqueoussolution (1 mL) of (NH₄)₂Ce(NO₃)₆ (0.035 g, 0.064 mmol) was addeddropwise to a THF solution (5 mL) of 4a (0.029 g, 0.032 mmol). Thereaction mixture immediately turned deep red. After 6 h the reactionmixture was poured into ether and washed with a saturated solution ofNaHCO₃ and water. The organic layer was dried with MgSO₄ and the solventremoved under reduced pressure. The crude product was purified by columnchromatography on silica gel (1:1 CH₂Cl₂/hexane) to afford 5a as a deepred solid in 80% yield (mp 86-87° C.).

6,7,10,11-tetrakis(2-ethylhexyloxy)triphenylene-1,4-dione (5b). Compound5b was prepared by the method described for 5a in 55% yield (mp=105-107°C.).

6,7,10,11-tetraethoxytriphenylene-1,4-dione (5c). Compound 5c wasprepared by the method described for 5a in 58% yield (mp 188-190° C.).

6,7,10,11-tetrakis(decyloxy)-1,4-di(2-trimethylsilylacetylene)triphenylene(6a). A hexane solution of ^(n)BuLi (2.77 mL, 1.57 M, 4.35 mmol) wasadded to a THF solution (15 mL) of trimethylsilylacetylene (0.615 mL,4.35 mmol) which had been precooled to −78° C. The mixture was allowedto warm to −10° C. and stirred at that temperature for 30 min. Thesolution was then cooled to −78° C. and a THF solution (10 mL) of 5a wasadded dropwise. During the addition the red color of the quinonedissipated. After the addition was complete the reaction mixture wasallowed to warm to room temperature and then stirred for an additional12 h. The reaction mixture was then poured into ether and enough diluteHCl was added to make the solution slightly acidic. The organic layerwas then quickly washed with several portions of water and dried withMgSO₄. The solvent was removed under reduced pressure and the remaininglight brown oil was dissolved in acetone (50 mL). To this solution wasadded dropwise a solution of SnCl₂.2 H₂O (0.851 g, 3.77 mmol) in 50%HOAc (10 mL). After 12 h the reaction mixture was poured into ether andwashed with water, a saturated solution of NaHCO₃ and again water. Theorganic layer was dried with MgSO₄ and the solvent was removed underreduced pressure. The product was purified by column chromatography onsilica gel (1:3 CH₂Cl₂/hexane) to afford 6a as a viscous yellow oil in38% yield.

6,7,10,11-tetrakis(2-ethylhexyloxy)triphenylene-1,4-di(2-trimethylsilyl)acetylene (6b). Compound 6b was prepared by the method described for 6ausing 5b as starting material. Compound 6b was obtained as a yellow oilin 97% yield.

Compound 6c was prepared by the method described for 6a using 5c asstarting material. (6c: R=ethyl)

6,7,10,11-tetrakis(decyloxy)-1,4-ethynyltriphenylene (7a). An aqueoussolution (1 mL) of KOH (0.30g) was added to a 1:1 THF/MeOH solution (20mL) of 6a (0.477 g, 0.475 mmol). The reaction mixture was allowed tostir for 12 h. It was then poured into ether and washed with water. Theorganic layer was dried with MgSO₄ and the solvent removed under reducedpressure. The product was purified by flash chromatography on silica gelusing a 1:3 CH₂Cl₂/hexane solvent mixture. Compound 7a was obtained as acolorless solid in 81% yield (mp 68-69° C.).

6,7,10,11-tetrakis(2-ethylhexyloxy)-1,4-ethynyltriphenylene (7b).Compound 7b was prepared by the method described for 7a using 6b asstarting material. Compound 7b was obtained as a yellow oil in 89%yield.

Compound 7c was prepared by the method described for 7a using 6c asstarting material. (7c: R=ethyl)

(10a). Compound 5a (0.516 g, 0.584 mmol) was dissolved in1,3-cyclohexadiene (10 mL). The mixture was heated to 80° C. for 12 h.The excess 1,3-cyclohexadiene was then removed under reduced pressure.The remaining viscous oil was transferred to a hydrogenation vessel (50mL capacity) along with CH₂Cl₂ (10 mL) and 10% Pd on carbon (10 mg).This mixture was degassed and then shaken under H₂ (40 psi) for 24 h.The reaction mixture was then filtered through a short plug of silicaand evaporated to dryness. The remaining solid was added to glacialacetic acid (40 mL) and heated to 100° C. Two drops of concentrated HBrwere added causing the solution to turn dark red. After 5 min an aqueoussolution (10 mL) of KBrO₃ (0.016 g, 0.096 mmol) was added and themixture was heated for an additional 10 min. The solution was allowed tocool and then extracted with two portions of CH₂Cl₂. The combinedorganic fractions were washed with water, dried with MgSO₄, andevaporated to dryness. The crude product was purified by columnchromatography on silica gel using a 1:9 ether/hexane solvent mixtureaffording 10a (R=n-Decyl) in 54% yield. By this method, the reactionproceeds through intermediates 8a and 9a.

(10b). Compound 10b (R=2-ethylhexyl) was prepared by the methoddescribed for 10a using 5b as starting material. The reaction proceedsthrough intermediates 8b and 9b. Compound 10b was obtained as a dark redviscous oil in 84% yield.

(12a). Compound 11a (R=n-Decyl) was prepared by the method described for6a using 10a as starting material. Compound 11a was purified by columnchromatography on silica gel using a 1:49 ether/hexane solvent mixture.The product was then converted to the diacetylene (12a: R=n-Decyl) bythe method described for 7a. The crude diacetylene was purified bycolumn chromatography on silica gel using a 1:19 ether/hexane solventmixture to afford 12a as a light orange solid in an overall 53% yield(mp 48.5-49.5° C.).

Compound 11b was prepared by the method described for 6a using 10b asstarting material. (11b: R=2-ethylhexyl)

(12b). Compound 12b (R=2-ethylhexyl) was prepared by the methoddescribed for 12a using 10b as starting material. Compound 12b wasobtained as a light yellow oil in an overall 56% yield from 10b.

1,4-diiodo -2,3,5,6-tetraalkoxybenzene:

To the solution of dibromotetraoctoxybenzene (3g, 4.0 mmol) in 20 mlTHF, n-Buli (10 ml, 16 mmol) was added via a syringe at −78 C. Thesolution was allowed to warm up slowly to 0 C and stirred at thistemperature for 40 min. Then I₂ crystals were poured into the solutionin two portions. After the purple solution was stirred at roomtemperature overnight, the excess I2 was removed by washing with 10%NaOH solution. The resulting colorless solution was dried with MgSO4 andconcentrated under vaccum to give a cotton-like solid (3 g, 91%).

1,4-Bis-[(trimethylsilyl)ethynyl]-2,3,5,6-tetraalkoxybenzene:

Under an argon atomsphere, 1,4-diiodo-2,3,5,6-tetraalkoxybenzene (1 g,1.19 mmol), Pd(PPh₃)₂Cl₂ (41 mg, 0.058 mmol), and CuI (22 mg, 0.12 mmol)were mixed in 10 mL HN(^(i)Pr)2 and 5 mL toluene.Trimethylsilylacetylene (0.42 ml, 2.97 mmol) was then introduced intothe mixture via a syringe. The resulting brown solution was heated to70° C. for two hours before it was cooled down and filtered to removeinsoluble iodium salts. The filtrate was concentrated, loaded onto asilica gel column and eluted with the mixture of hexanes and chloroform(10:1) to give a light yellow oil (0.78 g, 83%).

2,3,5,6-Tetraalkoxy -1,4-diacetylidebenzene:

A solution of potassium hydroxide (150 mg, 2.67 mmol) in 2 mL H₂O and 8mL MeOH was added dropwise to a solution of the yellow oil above in 16mL THF under magnetic stirring. After the solution was stirred at roomtemperature overnight, the solvent was removed under vacuum. The residuewas dissolved in CHCl₃, washed with H₂O and concentrated. The resultinggreen solid was chromatographed on a silica gel column with the mixtureof hexanes and chloroform to afford a off-white solid (0.52 g, 85%).

FIG. 32 shows examples of triphenylene-based polymers that can beprepared by the monomers described above using standardpalladium-catalyzed techniques.

EXAMPLE 6

Compounds 25, 27, 29, and 30 and polymers P2-P3 were synthesized andstudied according to the following general methods and instrumentation.All chemicals were of reagent grade from Aldrich Chemical Co. (St.Louis, Mo.), Strem Chemicals, Inc. (Newburyport, Mass.) or OakwoodProducts Inc. (West Columbia, S.C.) and used as received. All syntheticmanipulations were performed under an argon atmosphere using standardSchlenk line or drybox techniques unless otherwise noted.Dichloromethane and toluene were obtained from J. T. Baker and purifiedby passing through a Glasscontour dry solvent system. Glassware was ovendried before use. Column chromatography was performed using Baker 40 μmsilica gel. All organic extracts were dried over MgSO4 and filteredprior to removal with a rotary evaporator.

Tetrakis(triphenylphosphine)palladium(0) was purchased from Strem andused as received. Grubbs' 2nd generation catalyst[1,3-bis-(2,4,6-trimethylphenyl)-2-imidazolidin-ylidene)dichloro(phenylmethylene)-(tri-cyclohexylphosphine)ruthenium(II)]was purchased from Aldrich. Compounds 24, 28, and polymer P1 wereprepared according to procedures described in Kim et al., Macromolecules1999, 32, 1500-1507; Kim, et al., Nature 2001, 411, 1030-1034; Jones, etal., J. Chem. Soc. 1953, 713-715; Zhou, et al., J. Am. Chem. Soc., 1995,117, 12593; and Yang, et al., J. Am. Chem. Soc. 1998, 120, 11864-11873.Compound 31 was purchased from Nomadics Inc. (Stillwater, Okla.).

¹H NMR, ¹³C NMR, and ¹⁹F NMR spectra were obtained on Varian Mercury(300 MHz), Bruker Avance-400 (400 MHz), and Varian Inova (500 MHz)instruments. NMR chemical shifts are referenced to CHC¹³/TMS (7.27 ppmfor ¹H, 77.23 ppm for ¹³C). For ¹⁹F NMR spectra, trichlorofluoromethanewas used as an external standard (0 ppm) and upfield shifts are reportedas negative values. Mass spectra (MS) were obtained at the MITDepartment of Chemistry Instrumentation Facility (DCIF) using apeak-matching protocol to determine the mass and error range of themolecular ion.

All polymer solutions were filtered through 0.45 micron syringe filtersprior to use. Polymer molecular weights were determined at roomtemperature on a HP series 1100 GPC system in THE at 1.0 mL/min (1 mg/mLsample concentrations) equipped with a diode array detector (254 nm and450 nm) and a refractive index detector. Polymer molecular weights arereported relative to polystyrene standards. Polymer thin films werespin-cast from a 1 mg/mL polymer solution in chloroform at 2000 rpm ontomicroscope cover slips (18×18 mm) or on the inside of glass capillaries(for FIDO experiments).

UV/vis spectra were recorded on an Agilent 8453 diode-arrayspectrophotometer and corrected for background signal with either asolvent-filled cuvette (for solution measurements) or a clean glasscover slip (for thin film measurements). Emission spectra were acquiredon a SPEX Fluorolog-τ3 fluorometer (model FL-321, 450 W Xenon lamp)using either right angle detection (solution measurements) or front facedetection (thin film measurements). Fluorescence quantum yields ofsolutions were determined by comparison to appropriate standards and arecorrected for solvent refractive index and absorption differences at theexcitation wavelength. Time resolved fluorescence measurements wereperformed at the MIT Institute for Solider Nanotechnologies (Cambridge,Mass.) by exciting solution and thin film samples with 180 femtosecondpulses at 392 nm, the doubled output of a Coherent RegA Ti:Sapphireamplifier operating at 250 kHz. The resulting fluorescence wasspectrally and temporally resolved with a Hamamatsu C4770 Streak Camerasystem.

Melting points were measured with a Meltemp II apparatus and arereported uncorrected.

EXAMPLE 7

Compound 25 was synthesized according to the following method. Into a 25mL roundbottom flask, fitted with a refluxing condenser and a magneticstirring bar, were added 0.90 g (1.8 mmol) of 1, 0.87 g (5.8 mmol) of5-bromo-1-pentene, 0.30 g (2.2 mmol) of potassium carbonate, 0.12 g (0.7mmol) of potassium iodide, and 20 mL of 2-butanone. The suspension washeated to reflux for 18 hours. After cooling to room temperature, water(50 mL) and ethyl ether (50 mL) were added. The organic layer wasextracted into ethyl ether (3×50 mL), washed with water (3×50 mL) anddried to yield a green oil. The crude product was purified by columnchromatography (0-10% CH₂Cl₂ in hexanes) to yield 0.78 g (76%) of acolorless crystalline solid. mp: 293° C. ¹H NMR (300 MHz, CDCl₃) δ: 7.18(s, 2H), 5.80-5.87 (m, 1H), 5.05-5.14 (m, 1H), 5.00-5.05 (m, 1H), 3.94(dd, 4H, J=6, 12 Hz), 2.25-2.35 (m, 2H), 1.85-1.95 (m, 2H), 1.75-1.85(m, 2H), 1.43-1.55 (m, 4H), 1.23-1.44 (m, 10H), 0.85-0.92 (m, 3H). ¹³CNMR (75 MHz, CDCl₃) δ: 153.1, 152.9, 137.9, 122.9, 122.8, 115.6, 86.5,86.4, 70.5, 69.6, 32.1, 30.3, 29.8, 29.7, 29.5, 29.4, 29.3, 28.5, 26.2,22.9, 14.4. MS (EI): calcd for C₂₁H₃₂I₂O₂ (M⁺), 570.0486; found570.0460.

EXAMPLE 8

Compound 27 was synthesized according to the following method. Into a 25mL Schlenk tube with a magnetic stirring bar were added 0.10 g (0.2mmol) of compound 25, and 0.01 g (0.01 mmol) of Grubbs' 2nd generationcatalyst. A solution of1,1,1-trifluoro-2-(trifluoromethyl)-pent-4-en-2-ol (compound 26) 0.37 g(1.8 mmol) in 0.5 mL, CH₂Cl₂ was added and the reaction mixture washeated to 65° C. for 18 hours. After cooling to room temperature, thesolvent was removed and the crude product was purified by columnchromatography (0-10% ethyl acetate in hexanes) to yield 0.09 g (67%) ofa colorless solid. mp: 51-52° C. ¹H NMR (500 MHz, CDCl₃) δ: 7.18 (m,2H), 5.82-5.94 (m, 1H), 5.48-5.56 (m, 111), 3.94 (m, 4H), 2.94 (s, 1H),2.70 (d, 2H, J=8 Hz), 2.34-2.42 (dd, 2H), J=7, 14), 1.881.96 (m, 2H),1.78-1.84 (m, 2H), 1.46-1.54 (m, 2H), 1.25-1.40 (m, 12 H), 0.85-0.92 (m,3H). ¹³C NMR (125 MHz, CDCl₃) δ: 153.3, 152.7, 139.7, 123.1, 122.9,120.2, 86.5, 86.4, 70.5, 69.6, 33.8, 32.1, 29.8, 29.7, 29.6, 29.5, 29.4,29.3, 28.7, 26.2, 24.1, 22.9, 14.3. ¹⁹F NMR (282 MHz, CDCl₃): −76.9,−77.1 (two isomers). MS (EI): calcd for C₂₅H₃₄F₆I₂O₃ (M⁺), 750.0496;found 750.0478.

EXAMPLE 9

Compound 29 was synthesized according to the following method. Into a 25mL roundbottom flask, fitted with a refluxing condenser and a magneticstirring bar, were added 0.20 g (0.6 mmol) of 5, 0.50 g (3.4 mmol) of5-bromo-1-pentene, 0.20 g (1.4 mmol) of potassium carbonate, 0.08 g (0.5mmol) of potassium iodide, and 6 mL, of 2-butanone. The suspension washeated to reflux for 18 hours. After cooling to room temperature, water(50 mL) and ethyl ether (50 mL) were added. The organic layer wasextracted into ethyl ether (3×50 mL), washed with water (3×50 mL) anddried to yield a green oil. The crude product was purified by columnchromatography (0-5% ethyl acetate in hexanes) to yield 0.23 g (85%) ofcolorless crystals. mp: 41-42° C. ¹NMR (300 MHz, CDCl₃) δ: S 7.18 (s,2H), 5.80-5.95 (m, 2H), 5.05-5.14 (m, 2H), 4.98-5.05 (m, 2H), 3.95 (t,4H, J=6), 2.26-2.37 (dd, 4H, J=7, 14), 1.86-1.98 (m, 4H). ¹³C NMR (75MHz, CDCl₃) δ: 152.9, 137.8, 122.9 115.6, 86.5, 69.5, 30.3, 28.5. MS(ESI): calcd for C₁₆H₂₀I₂O₂ (M+Na)⁺, 520.9445; found 520.9455.

EXAMPLE 10

Compound 30 was synthesized according to the following method. Into a 50mL Schlenk tube with a magnetic stirring bar were added 0.50 g (1.0mmol) of compound 29, and 0.08 g (0.1 mmol) of Grubbs' 2nd generationcatalyst. A solution of1,1,1-trifluoro-2-(trifluoromethyl)-pent-4-en-2-ol (compound 26) 3.13 g(15.0 mmol) in 2.5 mL, CH₂Cl₂ was added and the reaction mixture washeated to 65° C. for 48 hours. After cooling to room temperature, thesolvent was removed and the crude product was purified by columnchromatography (0-33% ethyl acetate in hexanes) to yield an oily paste.Trituration with hexanes afforded 0.1 g (12%, first crop) of colorlesscrystals. mp: 125-126° C. ¹H NMR (400 MHz, CDCl₃) δ: 7.17 (s, 2H),5.80-5.88 (m, 2H), 5.48-5.55 (m, 2H), 3.96 (t, 4H, J=6 Hz), 2.94 (s,2H), 2.69-2.71 (d, 4H, J=8 Hz), 2.34-2.42 (dd, 4H, J=7, 14), 1.90-1.94(m, 4H). ¹³C NMR (100 MHz, CDCl₃) δ: 153.0, 139.7, 123.1, 120.3, 86.5,69.5, 33.7, 29.4, 28.7. ¹⁹F NMR (282 MHz, CDCl₃) δ: −76.9. MS (ESI):calcd for C₂₄H₂₄F₁₂I₂O₄ (M+Na)⁺, 880.9465; found 880.9459.

EXAMPLE 11

A general procedure for the synthesis of polymers P2 and P3 isillustrated by the synthesis of polymer P2, as described below. PolymerP3 was prepared in a similar manner from monomers 30 and 31. Allpolymers were characterized by ¹H and ¹⁹F NMR spectroscopy, gelpermeation chrmoatography (GPC), as well as UV-VIS, and fluorescencespectroscopy.

Into a 25 mL Schlenk tube with a magnetic stirring bar were addedcompound 4 (15 mg, 0.02 mmol), compound 5 (9.7 mg, 0.02 mmol), and smallamounts of copper iodide (<1 mg), and Pd(PPh₃)₄ (<1 mg). A deoxygenatedsolution of 3:2 (v/v) 4 Solvents were deoxygenated by vigorous argonbubbling for 20 minutes. toluene/diisopropylamine (0.750 mL) was thenadded. The tube was sealed and heated to 65° C. for 72 hours. Aftercooling to room temperature, the reaction mixture was precipitated byslow addition to 20 mL of methanol. The precipitate was isolated bycentrifugation and decantation of the supernatant. The precipitate waswashed with several 20 mL portions of methanol to remove any shortoligomers. The material was dried under vacuum to yield a yellow solid(17 mg, 87%).

P2: GPC (THF): M_(n)=17K, M_(w)=37K. ¹H NMR (300 MHz, CDCl₃) δ:7.40-7.55 (aromatic C—H), 6.96-7.10 (aromatic C—H), 5.90-6.20 (iptycenebridgehead C—H), 5.60-5.78 (olefinic C—H), 5.30-5.45 (olefinic C—H),4.38-4.55 (aliphatic C—H), 4.15-4.32 (aliphatic C—H), 2.65-3.05(aliphatic C—H), 2.43-2.58 (aliphatic C—H), 2.18-2.32 (aliphatic C—H),1.68-1.80 (aliphatic C—H), 1.35-1.68 (aliphatic C—H), 1.10-1.35(aliphatic C—H), 0.78-0.95 (aliphatic C—H). 8. 1917 NMR (282 MHz,CDCl3): 6 −76.8, −77.0. (two isomers)

P3: (75%) GPC (THF): M_(n)=26K, M_(w)=60K. ¹H NMR (300 MHz, CDCl₃) δ:7.44-7.52 (aromatic C—H), 6.96-7.09 (aromatic C—H), 6.02-6.14 (iptycenebridgehead C—H), 5.62-5.78 (olefinic C—H), 5.28-5.42 (olefinic C—H),4.42-4.52 (aliphatic C—H), 2.88-2.98 (aliphatic C—H), 2.75-2.80(aliphatic C—H), 2.44-2.56 (aliphatic C—H), 2.18-2.30 (aliphatic C—H).1917 NMR (282 MHz, CDCl3): 8 −76.9, −77.0 (two isomers).

EXAMPLE 12

The photo-physical properties of polymers P1, P2, and P3 were studiedand are summarized in Table 1. Polymer P1, a similar PPE of comparablemolecular weight, polymer P1, which presents only simpleunfunctionalized alkoxy-substituted side-chains, was studied forcomparison

Quantum yields and fluorescence lifetimes of polymers P1, P2, and P3were measured as solutions in CHCl₃. Solution-state fluorescence quantumyields are reported relative to an equi-absorbing solution of quininesulfate (Φ_(F)=0.53 in 0.1 N H₂SO₄). The reported fluorescence lifetimesare fit to a single-exponential function.

Upon comparing the photo-physical properties of polymers P1, P2, and P3,the pendant HFIP groups do not appear to significantly affect thephoto-physical properties of polymers P2 and P3, as they are bothsimilar to polymer P1 in terms of solution and solid-state absorptionand emission spectra, as well as solution-state fluorescence quantumyields and fluorescence lifetimes.

TABLE 1 Summary of Photophysical Data for Polymers P1, P2, and P3^(a)Abs λ_(max) (nm) Em λ_(max) (nm) Polymer CHCl₃ (film) CHCl₃ (film) Φ_(F)^(b) τ (ns)^(c) P1 413 (454) 452 (463) 0.51 0.6 P2 413 (445) 452 (462)0.63 0.5 P3 401 (405) 449 (457) 0.67 0.6

EXAMPLE 13

In order to determine the effect of the pendant HFIP groups on theperformance of PPE-based fluorescent chemosensors, FIDO 4TD, acommercial fluorescence-based vapor sensor designed and manufactured byNomadics Inc. (Stillwater, Okla.), was employed. The Fido sensormeasures the real-time fluorescence intensity of a conjugated polymerfilm as it is exposed to various analyte vapors.

For the FIDO experiments, polymer films of P1, P2, and P3, werespin-cast onto the inside of heavy-walled glass capillaries (GarnerGlass Co., Claremont, Calif.) from 1 mg/mL CHCl₃ solutions at 700 rpmfor 1 minute, and the emission of the films was monitored while analytevapors were passed through the capillary. Fluorescence quenchingexperiments were performed with the following settings: inlettemperature (135° C.), polymer temperature (20° C.), flow rate (35 ccm).Equilibrium vapor pressures of the analytes were delivered to the sensorby placing small quantities (=20 mg) of each analyte, along with a smallpiece of cotton guaze, into a 20 mL glass vial and capping the vial. Atequilibrium, the analyte vapor from the head-space of these vials servedas a convenient vapor source for the FIDO experiments. For each polymer,5-10 spin-coated capillaries were prepared and each was subjected torepeated exposures of each analyte vapor (1 second exposures were usedfor DNT, 3 second exposures were used for all other analytes). In thecases where the fluorescence response would become saturated from asingle exposure, fresh capillaries coated with the polymer would be usedeach time.

The responses of P1, P2, and P3 to vapors of 2,4-dinitrotoluene (DNT),4-aminopyridine (4AP), N,N′-(dimethylamino)pyridine (DMAP), pyridine(PYR), and 2,4-dichloropyrimidine (DCPYRIM) were evaluated by monitoringthe change in fluorescence intensity upon drawing analyte vapor throughthe capillary at a flow rate of 35 mL/min. The equilibrium vaporpressures of the analytes are shown in Table 2. Upon removal of analytevapor source, ambient air was pulled through the capillary. FIG. 37shows the average changes in fluorescence emission intensity uponrepeated exposures of polymers P1, P2, P3 to equilibrium vapor pressuresof various analytes (1 second exposures for DNT, 3 second exposures forall other analytes). A negative response indicates quenching of polymerfluorescence intensity upon exposure to the analyte vapor, while apositive response indicates an increase in polymer fluorescenceintensity upon exposure to the analyte vapor. The error bars representone standard deviation. FIG. 38 shows the (a) real-time fluorescenceresponse of (a) polymer P1 to five separate 3 second exposures topyridine vapor, (b) polymer P2 to a single 3 second exposure to pyridinevapor, and (c) polymer P3 to a single 3 second exposure to pyridinevapor.

TABLE 2 Equilbrium vapor pressure of analytes Analyte Equilibrium vaporpressure 2,4-dinitrotoluene 1.47 × 10⁻⁴ mmHg at 22° C. (0.2 ppm)4-aminopyridine 3.70 × 10⁻⁴ mmHg at 25° C. (0.5 ppm)N,N′-dimethylamino-pyridine 1.00 mmHg at 25° C. (1300 ppm) pyridine 20.8mmHg at 25° C. (27000 ppm) 2,4-dichloro-pyrimidine 2.98 × 10⁻¹ mmHg at25° C. (390 ppm)

The presence of HFIP groups was observerd to generally increase thesensitivity of P2 and P3 relative to P1. The differences were mostprofound in analytes that display the strongest hydrogen bondingbehavior. For example, all three polymers demonstrated similar quenchingresponses to the weak hydrogen bonding, but strongly electron deficientaromatic analyte, DNT. The very strong electrostatic interaction betweenthis analyte and the electron-rich PPEs appeared to overwhelm any effectof HFIP substitution in polymers P2 and P3. Pyridine, on the other hand,possesses much weaker electrostatic interactions with the PPEs andpolymer P1 showed 10-12% increases in fluorescence intensity uponexposure to pyridine vapor as shown in FIG. 38A (5 separate 3 sec.exposures). The increased fluorescence emission intensity wasimmediately lost upon removal of the pyridine vapor source, likely dueto swelling that reduces inter-chain interactions and increases the thinfilm quantum yield of the polymer. The rapid reversion of the initialfluorescence intensity indicated a fairly weak interaction betweenpolymer P1 and the pyridine vapor. The response of P1 was in starkcontrast to that of P2 (FIG. 38B) and P3 (FIG. 38C), which bothdisplayed strong decreases in fluorescence intensity upon exposure topyridine vapor. Without wishing to be bound by theory, the quenchedfluorescence observed upon exposure to pyridine suggests that pyridineforms a hydrogen bond with the HFIP group of polymer P2 or P3, and thehydrogen-bonded pyridinium species is sufficiently electron-deficient toundergo PICT reactions or form charge transfer complexes with the PPE.This observation demonstrates that incorporation of HFIP groups, inaddition to enabling more favorable polymer/analyte interactions, canalso serve to modulate the electronic properties of some targetedanalytes.

The very slow recovery of the initial fluorescence intensity for P2(FIG. 38B) may be indicative of strong analyte/polymer interactions, asthe pyridine vapor appears to adsorb much more strongly to the HFIPsubstituted polymer P2 and remains bound for a significant period oftime after the initial exposure. The FIDO data for polymer P3 (FIG. 38C)revealed even stronger interactions with pyridine, and the fluorescencedid not appear to recover after removal of the vapor source. Otheranalytes such as 4-aminopyridine (4AP) vapor andN,N′-dimethylamino-pyridine (DMAP) vapor appeared to be tooelectron-rich to undergo PICT reactions with any of the PPEs. From theFIDO data, polymers P1, P2, and P3 were observed to have minimalresponses to both 4AP and DMAP. Similar to the responses observed forpyridine, a more electron-deficient analyte, DCPYRIM, also resulted in asignificant 20% quenching of fluorescence from the HFIP-substitutedpolymers P2 and P3, while polymer P1 only demonstrated a minimal quenchin fluorescence.

For some embodiments, polymer P2, which demonstrated at least someamount of reversibility in pyridine binding, appeared to be anattractive material for sensing applications since P2 can surviverepeated analyte exposures. However, polymer P3, which demonstratedirreversible binding with some analytes (pyridine, 2,4-dichloropyridine,and DNT to some extent), may also be an attractive sensory material forthe detection of trace compounds or those with extremely low vaporpressures. For such analytes, a long analyte exposure time could beemployed to increase the amount of the adsorbed analyte to higherlevels, since the greater HFIP content of P3 makes the analytedesorption process less favorable.

Those skilled in the art would readily appreciate that all parameterslisted herein are meant to be exemplary and that actual parameters willdepend upon the specific application for which the methods and apparatusof the present invention are used. It is, therefore, to be understoodthat the foregoing embodiments are presented by way of example only andthat, within the scope of the appended claims and equivalents thereto,the invention may be practiced otherwise than as specifically described.

1. A sensor, comprising: a luminescent polymer having the followingstructure,

wherein: R²⁷ and R²⁸ are independently alkyl, heteroalkyl, aryl,heteroaryl, or substituted derivatives thereof, wherein at least one ofR²⁷ and R²⁸ comprises a hydrogen-bond donor comprising the structure,

m is at least 1; and n is at least 1, wherein the hydrogen-bond donor iscapable of interacting with an analyte to form a complex between thehydrogen-bond donor and the analyte, the complex being capable ofinteracting with the luminescent polymer via a photoinduced chargetransfer reaction and causing the luminescent polymer to signal thepresence of the analyte, wherein, in the absence of the hydrogen-bonddonor, the analyte is less capable of interacting with the luminescentpolymer.
 2. A sensor as in claim 1, wherein the hydrogen-bond donor iscapable of forming a hydrogen bond with the analyte to form the complex.3. A sensor as in claim 1, wherein the complex is a charge transfercomplex.
 4. A sensor as in claim 1, wherein the analyte comprises aheterocycle comprising nitrogen.
 5. A sensor as in claim 1, wherein theanalyte is 2,4-dinitrotoluene, 4-aminopyridine,N,N′-dimethylamino-pyridine, pyridine, or 2,4-dichloro-pyrimidine.
 6. Asensor as in claim 1, wherein at least one of R²⁷ and R²⁸ has thestructure,


7. A sensor as in claim 1, further comprising a source of energyapplicable to the luminescent polymer to cause emission of radiation;and an emission detector positionable to detect the emission.
 8. Amethod for determination of an analyte, comprising: providing aluminescent polymer having the following structure,

wherein: R²⁷ and R²⁸ are independently alkyl, heteroalkyl, aryl,heteroaryl, or substituted derivatives thereof, wherein at least one ofR²⁷ and R²⁸ comprises a hydrogen-bond donor comprising the structure,

m is at least 1; and n is at least 1; exposing the luminescent polymerto a sample suspected of containing an analyte, wherein the analyte, ifpresent, interacts with the hydrogen-bond donor to cause a change in theluminescence of the polymer, the change caused by a photoinduced chargetransfer reaction between the luminescent polymer and the complex; anddetermining the change in the luminescence of the polymer, therebydetermining the analyte, wherein, in the absence of the hydrogen-bonddonor, the analyte produces a lower degree of change in the luminescenceof the polymer.
 9. A method as in claim 8, wherein the interactingcomprises forming a complex between the hydrogen-bond donor and theanalyte.
 10. A method as in claim 8, wherein the hydrogen-bond donorforms a hydrogen bond with the analyte to form the complex.
 11. A methodas in claim 9, wherein the complex is a charge transfer complex.
 12. Amethod as in claim 8, wherein the analyte has a reduction potentialwhich is made less negative upon its interaction with the hydrogen-bonddonor.
 13. A method as in claim 8, wherein the analyte is a heterocyclecomprising nitrogen.
 14. A method as in claim 8, wherein the changecomprises a decrease in luminescence intensity.
 15. A method as in claim8, wherein the change comprises an increase in luminescence intensity.16. A method as in claim 8, wherein the change comprises a change in thewavelength of the luminescence.